[
{"id": "stone_tools", "name": "Stone tools", "year": -3300000, "cat": "foundations", "wiki": "Stone tool", "req": [], "desc": "Knapped stone flakes and cores, the oldest known human technology."},
{"id": "control_of_fire", "name": "Control of fire", "year": -1000000, "cat": "foundations", "wiki": "Control of fire by early humans", "req": [], "desc": "Keeping and later making fire for heat, light, cooking and protection."},
{"id": "spear", "name": "Spear", "year": -400000, "cat": "military", "wiki": "Spear", "req": ["stone_tools"], "desc": "A pointed shaft used for hunting and fighting; among the earliest weapons."},
{"id": "cordage", "name": "Rope and cordage", "year": -70000, "cat": "foundations", "wiki": "Rope", "req": ["stone_tools"], "desc": "Twisted plant or animal fibers that bind, haul and lash."},
{"id": "clothing", "name": "Clothing", "year": -170000, "cat": "daily", "wiki": "Clothing", "req": ["stone_tools"], "desc": "Hides and later textiles worn for protection and warmth."},
{"id": "sewing_needle", "name": "Sewing needle", "year": -45000, "cat": "daily", "wiki": "Sewing needle", "req": ["stone_tools"], "desc": "An eyed bone needle for stitching fitted garments."},
{"id": "bow_and_arrow", "name": "Bow and arrow", "year": -70000, "cat": "military", "wiki": "Bow and arrow", "req": ["cordage", "stone_tools"], "desc": "A spring weapon that stores energy in a bent stave to launch arrows."},
{"id": "dugout_canoe", "name": "Dugout canoe", "year": -8000, "cat": "transport", "wiki": "Dugout canoe", "req": ["stone_tools", "control_of_fire"], "desc": "A boat hollowed from a single log; among the oldest watercraft found."},
{"id": "domestication_of_animals", "name": "Animal domestication", "year": -13000, "cat": "agriculture", "wiki": "Domestication of vertebrates", "req": [], "desc": "Breeding dogs, sheep, goats, cattle and horses under human control."},
{"id": "agriculture", "name": "Agriculture", "year": -10000, "cat": "agriculture", "wiki": "Neolithic Revolution", "req": ["stone_tools"], "desc": "Cultivation of domesticated crops, beginning the shift to settled life."},
{"id": "pottery", "name": "Pottery", "year": -18000, "cat": "materials", "wiki": "Pottery", "req": ["control_of_fire"], "desc": "Clay vessels hardened by fire for cooking and storage."},
{"id": "kiln", "name": "Kiln", "year": -6000, "cat": "materials", "wiki": "Kiln", "req": ["pottery"], "desc": "An enclosed oven reaching temperatures high enough for ceramics and lime."},
{"id": "weaving", "name": "Weaving", "year": -12000, "cat": "daily", "wiki": "Weaving", "req": ["cordage"], "desc": "Interlacing threads at right angles to make cloth."},
{"id": "mudbrick", "name": "Mudbrick", "year": -9000, "cat": "construction", "wiki": "Mudbrick", "req": ["agriculture"], "desc": "Sun-dried bricks of mud and straw, the material of the first towns."},
{"id": "irrigation", "name": "Irrigation", "year": -6000, "cat": "agriculture", "wiki": "Irrigation", "req": ["agriculture"], "desc": "Channeling water to fields to grow crops in dry land."},
{"id": "plough", "name": "Plough", "year": -4000, "cat": "agriculture", "wiki": "Plough", "req": ["agriculture", "domestication_of_animals"], "desc": "A draft-animal tool that turns soil for planting."},
{"id": "wheel", "name": "Wheel", "year": -3500, "cat": "transport", "wiki": "Wheel", "req": ["stone_tools"], "desc": "A disc rotating on an axle, used first for pottery and carts."},
{"id": "potters_wheel", "name": "Potter's wheel", "year": -4500, "cat": "materials", "wiki": "Potter's wheel", "req": ["pottery"], "desc": "A spinning turntable for shaping symmetric clay vessels."},
{"id": "cart", "name": "Cart", "year": -3500, "cat": "transport", "wiki": "Cart", "req": ["wheel", "domestication_of_animals"], "desc": "A wheeled vehicle pulled by draft animals."},
{"id": "sail", "name": "Sail", "year": -4000, "cat": "transport", "wiki": "Sail", "req": ["weaving", "dugout_canoe"], "desc": "A cloth surface that harnesses wind to propel a boat."},
{"id": "smelting", "name": "Smelting", "year": -5000, "cat": "materials", "wiki": "Smelting", "req": ["kiln"], "desc": "Extracting metal from ore with heat and a reducing agent such as charcoal."},
{"id": "bronze", "name": "Bronze", "year": -3300, "cat": "materials", "wiki": "Bronze", "req": ["smelting", "tin_smelting"], "desc": "A hard copper-tin alloy that gave its name to an age."},
{"id": "iron_working", "name": "Iron working", "year": -1200, "cat": "materials", "wiki": "Ferrous metallurgy", "req": ["smelting"], "desc": "Smelting and forging iron from its ores."},
{"id": "blast_furnace", "name": "Blast furnace", "year": -100, "cat": "materials", "wiki": "Blast furnace", "req": ["iron_working", "bellows"], "desc": "A tall furnace blown with air that produces liquid iron continuously."},
{"id": "cast_iron", "name": "Cast iron", "year": -500, "cat": "materials", "wiki": "Cast iron", "req": ["iron_working"], "desc": "High-carbon iron melted and poured into molds."},
{"id": "steel", "name": "Steel", "year": -1000, "cat": "materials", "wiki": "Steel", "req": ["iron_working"], "desc": "Iron alloyed with a controlled amount of carbon for strength and toughness."},
{"id": "glass", "name": "Glass", "year": -3500, "cat": "materials", "wiki": "Glass", "req": ["kiln"], "desc": "An amorphous solid made by melting sand with soda and lime."},
{"id": "writing", "name": "Writing", "year": -3200, "cat": "knowledge", "wiki": "History of writing", "req": ["agriculture"], "desc": "Recording language with marks, beginning with Sumerian cuneiform and Egyptian hieroglyphs."},
{"id": "numerals", "name": "Numeral systems", "year": -3400, "cat": "knowledge", "wiki": "Numeral system", "req": ["agriculture"], "desc": "Symbols for recording quantities, grown out of clay counting tokens."},
{"id": "alphabet", "name": "Alphabet", "year": -1800, "cat": "knowledge", "wiki": "Alphabet", "req": ["writing"], "desc": "A small set of letters standing for individual sounds."},
{"id": "calendar", "name": "Calendar", "year": -3000, "cat": "knowledge", "wiki": "Calendar", "req": ["agriculture", "numerals"], "desc": "A system for organizing days into months and years by sun and moon."},
{"id": "coinage", "name": "Coinage", "year": -600, "cat": "knowledge", "wiki": "Coin", "req": ["smelting", "writing"], "desc": "Standardized stamped metal pieces used as money."},
{"id": "papyrus", "name": "Papyrus", "year": -3000, "cat": "communication", "wiki": "Papyrus", "req": ["writing"], "desc": "A writing surface made from pressed papyrus reed pith."},
{"id": "paper", "name": "Paper", "year": 105, "cat": "communication", "wiki": "Paper", "req": ["writing"], "desc": "Sheets of pressed plant fiber pulp, first made in Han China."},
{"id": "lever", "name": "Lever", "year": -5000, "cat": "manufacturing", "wiki": "Lever", "req": [], "desc": "A rigid bar pivoting on a fulcrum to multiply force."},
{"id": "pulley", "name": "Pulley", "year": -1500, "cat": "manufacturing", "wiki": "Pulley", "req": ["wheel", "cordage"], "desc": "A wheel carrying a rope to change the direction and size of a force."},
{"id": "screw", "name": "Screw", "year": -250, "cat": "manufacturing", "wiki": "Screw mechanism", "req": ["lever"], "desc": "An inclined plane wrapped around a cylinder, converting rotation to linear force."},
{"id": "gear", "name": "Gear", "year": -300, "cat": "manufacturing", "wiki": "Gear", "req": ["wheel"], "desc": "Toothed wheels that mesh to transmit torque and change speed."},
{"id": "lathe", "name": "Lathe", "year": -1300, "cat": "manufacturing", "wiki": "Lathe", "req": ["cordage"], "desc": "A machine that spins a workpiece against a cutting tool."},
{"id": "geometry", "name": "Geometry", "year": -300, "cat": "knowledge", "wiki": "Euclid's Elements", "req": ["writing", "numerals", "surveying"], "desc": "The axiomatic study of shape and space, systematized by Euclid."},
{"id": "lime_mortar", "name": "Lime mortar", "year": -4000, "cat": "construction", "wiki": "Lime mortar", "req": ["kiln"], "desc": "Burnt limestone mixed with sand and water to bind masonry."},
{"id": "roman_concrete", "name": "Roman concrete", "year": -200, "cat": "construction", "wiki": "Roman concrete", "req": ["lime_mortar"], "desc": "Lime and volcanic ash concrete that built the Pantheon and harbors."},
{"id": "portland_cement", "name": "Portland cement", "year": 1824, "cat": "construction", "wiki": "Portland cement", "req": ["roman_concrete", "kiln", "hydraulic_lime"], "desc": "The hydraulic cement behind nearly all modern concrete."},
{"id": "water_wheel", "name": "Water wheel", "year": -300, "cat": "energy", "wiki": "Water wheel", "req": ["wheel", "gear"], "desc": "A wheel turned by flowing water to drive mills and machinery."},
{"id": "windmill", "name": "Windmill", "year": 644, "cat": "energy", "wiki": "Windmill", "req": ["gear", "sail"], "desc": "A wind-driven mill for grinding grain and pumping water."},
{"id": "movable_type", "name": "Movable type", "year": 1040, "cat": "communication", "wiki": "Movable type", "req": ["paper"], "desc": "Reusable individual characters arranged to print text."},
{"id": "printing_press", "name": "Printing press", "year": 1440, "cat": "communication", "wiki": "Printing press", "req": ["movable_type", "screw", "paper", "metal_casting"], "desc": "Gutenberg's press with cast metal type, enabling mass-produced books."},
{"id": "gunpowder", "name": "Gunpowder", "year": 850, "cat": "military", "wiki": "Gunpowder", "req": ["control_of_fire"], "desc": "An explosive mixture of saltpeter, sulfur and charcoal discovered in Tang China."},
{"id": "compass", "name": "Compass", "year": 1040, "cat": "instruments", "wiki": "Compass", "req": ["iron_working"], "desc": "A magnetized needle that points north, transforming navigation."},
{"id": "mechanical_clock", "name": "Mechanical clock", "year": 1280, "cat": "instruments", "wiki": "History of timekeeping devices", "req": ["gear", "verge_escapement"], "desc": "A weight-driven clock regulated by an escapement."},
{"id": "lens", "name": "Lens", "year": 1000, "cat": "instruments", "wiki": "Lens", "req": ["glass"], "desc": "Ground glass that focuses or spreads light by refraction."},
{"id": "telescope", "name": "Telescope", "year": 1608, "cat": "instruments", "wiki": "Telescope", "req": ["lens"], "desc": "An instrument that magnifies distant objects using lenses or mirrors."},
{"id": "microscope", "name": "Microscope", "year": 1620, "cat": "instruments", "wiki": "Microscope", "req": ["lens"], "desc": "An instrument that magnifies objects too small to see by eye."},
{"id": "hindu_arabic_numerals", "name": "Hindu–Arabic numerals", "year": 500, "cat": "knowledge", "wiki": "Hindu–Arabic numeral system", "req": ["numerals"], "desc": "Positional decimal notation with a symbol for zero."},
{"id": "algebra", "name": "Algebra", "year": 820, "cat": "knowledge", "wiki": "Algebra", "req": ["hindu_arabic_numerals"], "desc": "Solving equations with symbols for unknowns, named after al-Khwarizmi's book."},
{"id": "scientific_method", "name": "Scientific method", "year": 1620, "cat": "knowledge", "wiki": "Scientific method", "req": ["printing_press"], "desc": "Systematic observation, hypothesis and experiment."},
{"id": "calculus", "name": "Calculus", "year": 1670, "cat": "knowledge", "wiki": "Calculus", "req": ["algebra", "geometry", "analytic_geometry"], "desc": "The mathematics of change, developed by Newton and Leibniz."},
{"id": "classical_mechanics", "name": "Newtonian mechanics", "year": 1687, "cat": "knowledge", "wiki": "Newton's laws of motion", "req": ["calculus", "scientific_method"], "desc": "Newton's laws of motion and gravitation."},
{"id": "vacuum_pump", "name": "Vacuum pump", "year": 1650, "cat": "instruments", "wiki": "Vacuum pump", "req": ["scientific_method"], "desc": "A device that removes gas from a sealed volume, first built by von Guericke."},
{"id": "coal_mining", "name": "Coal mining", "year": 1000, "cat": "energy", "wiki": "Coal mining", "req": ["iron_working"], "desc": "Extracting coal from the ground, the fuel of industrialization."},
{"id": "coke_fuel", "name": "Coke smelting", "year": 1709, "cat": "materials", "wiki": "Coke (fuel)", "req": ["coal_mining", "blast_furnace"], "desc": "Baked coal that let Abraham Darby smelt iron without charcoal."},
{"id": "steam_engine", "name": "Steam engine", "year": 1712, "cat": "energy", "wiki": "Newcomen atmospheric engine", "req": ["cast_iron", "vacuum_pump", "coal_mining"], "desc": "Newcomen's atmospheric engine, the first practical machine to turn heat into work."},
{"id": "watt_steam_engine", "name": "Watt steam engine", "year": 1776, "cat": "energy", "wiki": "Watt steam engine", "req": ["steam_engine", "boring_machine"], "desc": "James Watt's separate-condenser engine, which made steam power efficient."},
{"id": "boring_machine", "name": "Cylinder boring machine", "year": 1775, "cat": "manufacturing", "wiki": "Boring (manufacturing)", "req": ["lathe", "cast_iron"], "desc": "Wilkinson's machine for boring accurate cylinders in cast iron."},
{"id": "machine_tools", "name": "Machine tools", "year": 1800, "cat": "manufacturing", "wiki": "Machine tool", "req": ["lathe", "boring_machine", "watt_steam_engine"], "desc": "Powered machines for precisely cutting and shaping metal."},
{"id": "interchangeable_parts", "name": "Interchangeable parts", "year": 1800, "cat": "manufacturing", "wiki": "Interchangeable parts", "req": ["machine_tools"], "desc": "Components made to tolerances so that any one fits any assembly."},
{"id": "factory_system", "name": "Factory system", "year": 1771, "cat": "manufacturing", "wiki": "Factory system", "req": ["water_wheel"], "desc": "Centralized, power-driven production with wage labor."},
{"id": "thermodynamics", "name": "Thermodynamics", "year": 1824, "cat": "knowledge", "wiki": "Thermodynamics", "req": ["watt_steam_engine", "classical_mechanics"], "desc": "The science of heat, work and energy, spurred by the steam engine."},
{"id": "modern_chemistry", "name": "Modern chemistry", "year": 1789, "cat": "materials", "wiki": "Chemical revolution", "req": ["scientific_method", "analytical_balance"], "desc": "Lavoisier's quantitative chemistry of elements and compounds."},
{"id": "distillation", "name": "Distillation", "year": 100, "cat": "materials", "wiki": "Distillation", "req": ["glass", "pottery"], "desc": "Separating liquids by boiling and condensing them."},
{"id": "voltaic_pile", "name": "Electric battery", "year": 1800, "cat": "electronics", "wiki": "Voltaic pile", "req": ["modern_chemistry"], "desc": "Volta's stack of zinc and copper discs, the first steady source of current."},
{"id": "electrolysis", "name": "Electrolysis", "year": 1800, "cat": "materials", "wiki": "Electrolysis", "req": ["voltaic_pile"], "desc": "Driving chemical reactions with electric current."},
{"id": "electromagnetism", "name": "Electromagnetism", "year": 1820, "cat": "knowledge", "wiki": "Electromagnetism", "req": ["voltaic_pile"], "desc": "Ørsted's discovery that currents create magnetic fields."},
{"id": "electromagnet", "name": "Electromagnet", "year": 1824, "cat": "electronics", "wiki": "Electromagnet", "req": ["electromagnetism"], "desc": "A coil of wire that becomes a magnet when current flows."},
{"id": "electric_motor", "name": "Electric motor", "year": 1832, "cat": "electronics", "wiki": "Electric motor", "req": ["electromagnet"], "desc": "A machine converting electrical energy to rotation."},
{"id": "electric_generator", "name": "Electric generator", "year": 1831, "cat": "energy", "wiki": "Electric generator", "req": ["electromagnetism", "faradays_law"], "desc": "A machine converting rotation to electricity by induction, after Faraday."},
{"id": "telegraph", "name": "Electrical telegraph", "year": 1837, "cat": "communication", "wiki": "Electrical telegraph", "req": ["voltaic_pile", "electromagnet", "relay"], "desc": "Sending coded messages over wires, first commercialized by Cooke, Wheatstone and Morse."},
{"id": "maxwell_equations", "name": "Electromagnetic theory", "year": 1865, "cat": "knowledge", "wiki": "Maxwell's equations", "req": ["electromagnetism", "calculus", "faradays_law"], "desc": "Maxwell's unification of electricity, magnetism and light."},
{"id": "telephone", "name": "Telephone", "year": 1876, "cat": "communication", "wiki": "Telephone", "req": ["telegraph", "electromagnet", "faradays_law"], "desc": "Transmitting speech as electrical signals over wire."},
{"id": "light_bulb", "name": "Incandescent light bulb", "year": 1879, "cat": "electronics", "wiki": "Incandescent light bulb", "req": ["vacuum_pump", "electric_generator", "glass"], "desc": "A glowing filament in a vacuum bulb; the first practical electric light."},
{"id": "transformer", "name": "Transformer", "year": 1885, "cat": "electronics", "wiki": "Transformer", "req": ["electromagnet", "faradays_law"], "desc": "A device that changes AC voltage via mutual induction."},
{"id": "electrical_grid", "name": "Electrical grid", "year": 1882, "cat": "energy", "wiki": "Electrical grid", "req": ["electric_generator", "light_bulb"], "desc": "Networks generating and delivering electricity to consumers."},
{"id": "photography", "name": "Photography", "year": 1826, "cat": "communication", "wiki": "Photography", "req": ["camera_obscura", "modern_chemistry"], "desc": "Recording images chemically on light-sensitive surfaces."},
{"id": "camera_obscura", "name": "Camera obscura", "year": 1000, "cat": "instruments", "wiki": "Camera obscura", "req": [], "desc": "A darkened chamber where a pinhole projects an image of the outside."},
{"id": "vulcanization", "name": "Vulcanized rubber", "year": 1839, "cat": "materials", "wiki": "Vulcanization", "req": ["modern_chemistry", "natural_rubber"], "desc": "Curing rubber with sulfur so it stays elastic and durable."},
{"id": "oil_well", "name": "Oil drilling", "year": 1859, "cat": "energy", "wiki": "Oil well", "req": ["steam_engine", "steel", "drilling_rig"], "desc": "Drilled wells that tapped petroleum at scale, starting in Pennsylvania."},
{"id": "oil_refining", "name": "Oil refining", "year": 1856, "cat": "energy", "wiki": "Oil refinery", "req": ["distillation"], "desc": "Separating crude oil into kerosene, gasoline and other products."},
{"id": "bessemer_process", "name": "Bessemer process", "year": 1856, "cat": "materials", "wiki": "Bessemer process", "req": ["steel", "cast_iron"], "desc": "Blowing air through molten pig iron to make cheap steel in bulk."},
{"id": "steam_locomotive", "name": "Steam locomotive", "year": 1804, "cat": "transport", "wiki": "Steam locomotive", "req": ["watt_steam_engine", "machine_tools"], "desc": "A steam engine on wheels pulling trains along rails."},
{"id": "railway", "name": "Railway", "year": 1825, "cat": "transport", "wiki": "Rail transport", "req": ["steam_locomotive", "iron_working", "wrought_iron"], "desc": "Public rail networks beginning with the Stockton and Darlington."},
{"id": "steamship", "name": "Steamship", "year": 1807, "cat": "transport", "wiki": "Steamship", "req": ["watt_steam_engine"], "desc": "A ship propelled by steam engines rather than sail."},
{"id": "internal_combustion_engine", "name": "Internal combustion engine", "year": 1860, "cat": "energy", "wiki": "Internal combustion engine", "req": ["machine_tools", "oil_refining", "thermodynamics", "induction_coil"], "desc": "An engine burning fuel inside its cylinders, perfected by Otto and Diesel."},
{"id": "automobile", "name": "Automobile", "year": 1886, "cat": "transport", "wiki": "Car", "req": ["internal_combustion_engine", "vulcanization", "steel", "four_stroke_engine", "carburetor"], "desc": "A self-propelled road vehicle, starting with Benz's Patent-Motorwagen."},
{"id": "assembly_line", "name": "Assembly line", "year": 1913, "cat": "manufacturing", "wiki": "Assembly line", "req": ["interchangeable_parts", "electric_motor"], "desc": "Moving work past stationed workers, as in Ford's Highland Park plant."},
{"id": "aluminium_smelting", "name": "Aluminium smelting", "year": 1886, "cat": "materials", "wiki": "Hall–Héroult process", "req": ["electrolysis", "electric_generator"], "desc": "Electrolytic reduction of alumina that made aluminium cheap."},
{"id": "airplane", "name": "Airplane", "year": 1903, "cat": "aerospace", "wiki": "Airplane", "req": ["internal_combustion_engine", "aerodynamics", "lilienthal_glider", "wing_warping", "aircraft_engine", "aeronautical_propeller", "wind_tunnel"], "desc": "A powered, fixed-wing aircraft, first flown by the Wright brothers."},
{"id": "aerodynamics", "name": "Aerodynamics", "year": 1871, "cat": "knowledge", "wiki": "Aerodynamics", "req": ["classical_mechanics"], "desc": "The study of air in motion and forces on bodies within it."},
{"id": "rocket", "name": "Rocket", "year": 1232, "cat": "aerospace", "wiki": "Rocket", "req": ["gunpowder"], "desc": "A vehicle propelled by reaction mass, first as Chinese fire arrows."},
{"id": "liquid_rocket", "name": "Liquid-propellant rocket", "year": 1926, "cat": "aerospace", "wiki": "Liquid-propellant rocket", "req": ["rocket", "machine_tools", "thermodynamics", "rocket_equation", "de_laval_nozzle"], "desc": "Rockets burning liquid fuel and oxidizer, first flown by Robert Goddard."},
{"id": "jet_engine", "name": "Jet engine", "year": 1937, "cat": "aerospace", "wiki": "Jet engine", "req": ["gas_turbine", "airplane"], "desc": "A reaction engine that propels aircraft by a fast exhaust jet."},
{"id": "gas_turbine", "name": "Gas turbine", "year": 1903, "cat": "energy", "wiki": "Gas-turbine engine", "req": ["thermodynamics", "steel"], "desc": "A continuous-combustion engine driving a turbine with hot gas."},
{"id": "radio", "name": "Radio", "year": 1895, "cat": "communication", "wiki": "Radio", "req": ["maxwell_equations", "telegraph", "electromagnetic_waves", "induction_coil", "antenna"], "desc": "Communication by electromagnetic waves, pioneered by Marconi."},
{"id": "cathode_ray_tube", "name": "Cathode-ray tube", "year": 1897, "cat": "electronics", "wiki": "Cathode ray tube", "req": ["vacuum_pump", "electromagnetism"], "desc": "A vacuum tube steering electron beams onto a phosphor screen."},
{"id": "vacuum_tube", "name": "Vacuum tube", "year": 1904, "cat": "electronics", "wiki": "Vacuum tube", "req": ["light_bulb", "vacuum_pump", "thermionic_emission"], "desc": "An evacuated tube controlling electron flow; the first amplifier and switch."},
{"id": "television", "name": "Television", "year": 1927, "cat": "communication", "wiki": "Television", "req": ["cathode_ray_tube", "radio", "vacuum_tube", "photoelectric_effect"], "desc": "Transmitting moving images and sound to receivers."},
{"id": "radar", "name": "Radar", "year": 1935, "cat": "electronics", "wiki": "Radar", "req": ["radio", "vacuum_tube", "cathode_ray_tube"], "desc": "Detecting objects by reflected radio waves."},
{"id": "quantum_mechanics", "name": "Quantum mechanics", "year": 1925, "cat": "knowledge", "wiki": "Quantum mechanics", "req": ["maxwell_equations", "thermodynamics", "bohr_model", "plancks_law"], "desc": "The physics of atoms and subatomic particles."},
{"id": "semiconductor", "name": "Semiconductor physics", "year": 1931, "cat": "electronics", "wiki": "Semiconductor", "req": ["quantum_mechanics", "band_theory"], "desc": "Materials whose conductivity can be engineered, explained by band theory."},
{"id": "transistor", "name": "Transistor", "year": 1947, "cat": "electronics", "wiki": "Transistor", "req": ["semiconductor", "vacuum_tube"], "desc": "A solid-state amplifier and switch invented at Bell Labs."},
{"id": "photolithography", "name": "Photolithography", "year": 1955, "cat": "electronics", "wiki": "Photolithography", "req": ["photography", "modern_chemistry"], "desc": "Patterning microscopic features with light and photoresist."},
{"id": "integrated_circuit", "name": "Integrated circuit", "year": 1958, "cat": "electronics", "wiki": "Integrated circuit", "req": ["transistor", "photolithography"], "desc": "Many transistors fabricated together on one chip, by Kilby and Noyce."},
{"id": "microprocessor", "name": "Microprocessor", "year": 1971, "cat": "computing", "wiki": "Microprocessor", "req": ["integrated_circuit", "mosfet", "self_aligned_gate"], "desc": "A complete CPU on a single chip, beginning with the Intel 4004."},
{"id": "punched_card", "name": "Punched card", "year": 1804, "cat": "computing", "wiki": "Punched card", "req": ["paper", "jacquard_loom"], "desc": "Cards encoding data as holes, from Jacquard looms to tabulators."},
{"id": "boolean_algebra", "name": "Boolean algebra", "year": 1847, "cat": "knowledge", "wiki": "Boolean algebra", "req": ["algebra"], "desc": "George Boole's algebra of true and false, the logic of digital circuits."},
{"id": "electronic_computer", "name": "Electronic computer", "year": 1945, "cat": "computing", "wiki": "Computer", "req": ["vacuum_tube", "boolean_algebra", "punched_card"], "desc": "Programmable machines computing with electronic circuits, such as ENIAC and Colossus."},
{"id": "personal_computer", "name": "Personal computer", "year": 1974, "cat": "computing", "wiki": "Personal computer", "req": ["microprocessor"], "desc": "A computer cheap and small enough for one person to own."},
{"id": "packet_switching", "name": "Packet switching", "year": 1965, "cat": "computing", "wiki": "Packet switching", "req": ["electronic_computer", "telephone"], "desc": "Splitting data into routed packets, the basis of computer networks."},
{"id": "internet", "name": "Internet", "year": 1983, "cat": "computing", "wiki": "Internet", "req": ["packet_switching"], "desc": "The global network of networks running TCP/IP."},
{"id": "world_wide_web", "name": "World Wide Web", "year": 1991, "cat": "computing", "wiki": "World Wide Web", "req": ["internet", "hypertext"], "desc": "Tim Berners-Lee's system of linked hypertext documents over the internet."},
{"id": "hypertext", "name": "Hypertext", "year": 1965, "cat": "computing", "wiki": "Hypertext", "req": ["electronic_computer", "memex"], "desc": "Text containing links to other text."},
{"id": "mobile_phone", "name": "Mobile phone", "year": 1973, "cat": "communication", "wiki": "Mobile phone", "req": ["radio", "integrated_circuit", "telephone"], "desc": "A portable telephone working over a cellular radio network."},
{"id": "lithium_ion_battery", "name": "Lithium-ion battery", "year": 1991, "cat": "energy", "wiki": "Lithium-ion battery", "req": ["voltaic_pile", "modern_chemistry", "lithium_cobalt_oxide", "lithium_battery"], "desc": "A rechargeable battery shuttling lithium ions, commercialized by Sony."},
{"id": "smartphone", "name": "Smartphone", "year": 2007, "cat": "communication", "wiki": "Smartphone", "req": ["mobile_phone", "microprocessor", "lithium_ion_battery", "internet", "capacitive_touchscreen", "tft_lcd"], "desc": "A pocket computer with a touchscreen and mobile internet."},
{"id": "laser", "name": "Laser", "year": 1960, "cat": "instruments", "wiki": "Laser", "req": ["quantum_mechanics", "maser"], "desc": "A source of coherent light by stimulated emission."},
{"id": "nuclear_fission", "name": "Nuclear fission", "year": 1938, "cat": "knowledge", "wiki": "Nuclear fission", "req": ["quantum_mechanics", "neutron"], "desc": "The splitting of heavy nuclei, discovered by Hahn, Strassmann and Meitner."},
{"id": "nuclear_reactor", "name": "Nuclear reactor", "year": 1942, "cat": "energy", "wiki": "Nuclear reactor", "req": ["nuclear_fission", "neutron", "synthetic_graphite"], "desc": "A controlled fission chain reaction, first achieved in Chicago Pile-1."},
{"id": "nuclear_weapon", "name": "Nuclear weapon", "year": 1945, "cat": "military", "wiki": "Nuclear weapon", "req": ["nuclear_fission", "nuclear_reactor"], "desc": "Bombs releasing energy from fission or fusion."},
{"id": "solar_cell", "name": "Solar cell", "year": 1954, "cat": "energy", "wiki": "Solar cell", "req": ["semiconductor", "pn_junction", "monocrystalline_silicon"], "desc": "A semiconductor device converting light directly to electricity."},
{"id": "bakelite", "name": "Synthetic plastic", "year": 1907, "cat": "materials", "wiki": "Bakelite", "req": ["modern_chemistry"], "desc": "Bakelite, the first fully synthetic plastic."},
{"id": "germ_theory", "name": "Germ theory of disease", "year": 1861, "cat": "medicine", "wiki": "Germ theory of disease", "req": ["microscope", "scientific_method"], "desc": "The understanding that microorganisms cause many diseases."},
{"id": "vaccination", "name": "Vaccination", "year": 1796, "cat": "medicine", "wiki": "Vaccination", "req": ["scientific_method"], "desc": "Jenner's smallpox vaccine, inducing immunity with a harmless agent."},
{"id": "anesthesia", "name": "General anesthesia", "year": 1846, "cat": "medicine", "wiki": "General anaesthesia", "req": ["modern_chemistry"], "desc": "Ether and chloroform made painless surgery possible."},
{"id": "penicillin", "name": "Penicillin", "year": 1928, "cat": "medicine", "wiki": "Penicillin", "req": ["germ_theory", "microbiological_culture"], "desc": "The first widely used antibiotic, discovered by Alexander Fleming."},
{"id": "x_ray", "name": "X-ray imaging", "year": 1895, "cat": "medicine", "wiki": "Radiography", "req": ["vacuum_pump", "photography", "electromagnetism"], "desc": "Imaging the body's interior with Röntgen's newly discovered rays."},
{"id": "dna_double_helix", "name": "DNA structure", "year": 1953, "cat": "biotech", "wiki": "Nucleic acid double helix", "req": ["x_ray_crystallography", "avery_experiment", "hershey_chase"], "desc": "Watson, Crick, Franklin and Wilkins revealed the double helix."},
{"id": "x_ray_crystallography", "name": "X-ray crystallography", "year": 1912, "cat": "instruments", "wiki": "X-ray crystallography", "req": ["x_ray"], "desc": "Determining atomic structures from X-ray diffraction patterns."},
{"id": "recombinant_dna", "name": "Recombinant DNA", "year": 1973, "cat": "biotech", "wiki": "Recombinant DNA", "req": ["dna_double_helix", "restriction_enzyme", "dna_ligase", "plasmid", "bacterial_transformation"], "desc": "Splicing DNA from different organisms, by Cohen and Boyer."},
{"id": "pcr", "name": "Polymerase chain reaction", "year": 1983, "cat": "biotech", "wiki": "Polymerase chain reaction", "req": ["dna_double_helix", "dna_polymerase", "oligonucleotide_synthesis"], "desc": "Kary Mullis's method for copying DNA millions of times."},
{"id": "dna_sequencing", "name": "DNA sequencing", "year": 1977, "cat": "biotech", "wiki": "DNA sequencing", "req": ["dna_double_helix", "dna_polymerase", "gel_electrophoresis", "radioactive_tracer"], "desc": "Reading the order of bases in DNA, starting with Sanger's method."},
{"id": "haber_process", "name": "Haber–Bosch process", "year": 1909, "cat": "agriculture", "wiki": "Haber process", "req": ["modern_chemistry", "steel", "catalysis"], "desc": "Synthesizing ammonia from air, the basis of nitrogen fertilizer."},
{"id": "refrigeration", "name": "Mechanical refrigeration", "year": 1834, "cat": "daily", "wiki": "Vapor-compression refrigeration", "req": ["thermodynamics", "steam_engine"], "desc": "Cooling by compressing and evaporating a refrigerant."},
{"id": "canning", "name": "Canning", "year": 1810, "cat": "agriculture", "wiki": "Canning", "req": ["glass", "iron_working"], "desc": "Preserving food by sealing it in airtight containers and heating."},
{"id": "artificial_intelligence", "name": "Artificial intelligence", "year": 1956, "cat": "computing", "wiki": "Artificial intelligence", "req": ["electronic_computer"], "desc": "Machines performing tasks that require intelligence, founded as a field at Dartmouth."},
{"id": "satellite", "name": "Artificial satellite", "year": 1957, "cat": "aerospace", "wiki": "Satellite", "req": ["liquid_rocket", "radio", "r7_rocket", "rocket_equation"], "desc": "An object placed in orbit, starting with Sputnik 1."},
{"id": "kite", "name": "Kite", "year": -500, "cat": "aerospace", "wiki": "Kite", "req": ["cordage", "weaving"], "desc": "A tethered wing of silk or paper on a frame, flown in ancient China; the first heavier-than-air craft."},
{"id": "bamboo_copter", "name": "Bamboo-copter", "year": -400, "cat": "aerospace", "wiki": "Bamboo-copter", "req": ["cordage"], "desc": "A Chinese toy rotor spun by hand or string that flies upward; an early demonstration of rotary-wing lift."},
{"id": "sky_lantern", "name": "Sky lantern", "year": 200, "cat": "aerospace", "wiki": "Sky lantern", "req": ["paper", "control_of_fire"], "desc": "A small paper hot-air balloon lifted by a flame, used in China for signalling; the principle behind the hot air balloon."},
{"id": "hot_air_balloon", "name": "Hot air balloon", "year": 1783, "cat": "aerospace", "wiki": "Hot air balloon", "req": ["sky_lantern", "weaving", "paper"], "desc": "The Montgolfier brothers' heated-air envelope that carried the first humans aloft in 1783."},
{"id": "gas_balloon", "name": "Hydrogen balloon", "year": 1783, "cat": "aerospace", "wiki": "Gas balloon", "req": ["hot_air_balloon"], "desc": "Jacques Charles's balloon filled with hydrogen, which floated longer and higher than hot air."},
{"id": "parachute", "name": "Parachute", "year": 1797, "cat": "aerospace", "wiki": "Parachute", "req": ["hot_air_balloon"], "desc": "A canopy that slows descent through drag; André-Jacques Garnerin made the first jumps from a balloon in 1797."},
{"id": "fixed_wing_aircraft", "name": "Fixed-wing aircraft concept", "year": 1804, "cat": "aerospace", "wiki": "Fixed-wing aircraft", "req": ["kite", "classical_mechanics"], "desc": "George Cayley's separation of lift, thrust and control, shown in his 1804 model glider; the basis of the airplane."},
{"id": "aeronautical_propeller", "name": "Aircraft propeller", "year": 1852, "cat": "aerospace", "wiki": "Propeller (aeronautics)", "req": ["screw", "steamship"], "desc": "A rotating airfoil blade that converts engine power into thrust, first used on Giffard's 1852 airship."},
{"id": "airship", "name": "Airship", "year": 1852, "cat": "aerospace", "wiki": "Airship", "req": ["gas_balloon", "steam_engine", "aeronautical_propeller"], "desc": "A steerable powered balloon; Henri Giffard flew a steam-driven one in 1852."},
{"id": "glider", "name": "Glider", "year": 1853, "cat": "aerospace", "wiki": "Glider (aircraft)", "req": ["fixed_wing_aircraft"], "desc": "An unpowered heavier-than-air craft; Cayley's 1853 glider carried a person across a valley."},
{"id": "ornithopter", "name": "Ornithopter", "year": 1870, "cat": "aerospace", "wiki": "Ornithopter", "req": ["classical_mechanics"], "desc": "A machine that flies by flapping wings; Gustave Trouvé's 1870 model was among the first to fly."},
{"id": "wind_tunnel", "name": "Wind tunnel", "year": 1871, "cat": "aerospace", "wiki": "Wind tunnel", "req": ["aerodynamics"], "desc": "A duct that blows air over models so lift and drag can be measured; first built by Francis Wenham in 1871."},
{"id": "airfoil", "name": "Cambered airfoil", "year": 1884, "cat": "aerospace", "wiki": "Airfoil", "req": ["wind_tunnel"], "desc": "A curved wing section, patented by Horatio Phillips in 1884, that produces far more lift than a flat plate."},
{"id": "de_laval_nozzle", "name": "De Laval nozzle", "year": 1888, "cat": "aerospace", "wiki": "De Laval nozzle", "req": ["thermodynamics", "steam_turbine"], "desc": "A converging-diverging nozzle that accelerates gas to supersonic speed; the standard shape of rocket nozzles."},
{"id": "lilienthal_glider", "name": "Lilienthal glider", "year": 1894, "cat": "aerospace", "wiki": "Lilienthal Normalsegelapparat", "req": ["glider", "airfoil"], "desc": "Otto Lilienthal's hang glider, flown hundreds of times; the first aircraft built in series and a model for the Wrights."},
{"id": "biplane", "name": "Biplane", "year": 1896, "cat": "aerospace", "wiki": "Biplane", "req": ["glider"], "desc": "A two-wing layout braced as a truss, strong and light; used by Chanute's glider and the Wright Flyer."},
{"id": "wing_warping", "name": "Wing warping", "year": 1899, "cat": "aerospace", "wiki": "Wing warping", "req": ["biplane"], "desc": "Twisting the wingtips to control roll, devised by the Wright brothers in 1899."},
{"id": "zeppelin", "name": "Rigid airship", "year": 1900, "cat": "aerospace", "wiki": "Zeppelin", "req": ["airship", "internal_combustion_engine", "aluminium_smelting"], "desc": "Ferdinand von Zeppelin's airship with a metal framework holding gas cells; used for the first airline service in 1910."},
{"id": "rocket_equation", "name": "Tsiolkovsky rocket equation", "year": 1903, "cat": "aerospace", "wiki": "Tsiolkovsky rocket equation", "req": ["classical_mechanics", "calculus"], "desc": "Konstantin Tsiolkovsky's relation between exhaust velocity, mass ratio and speed gain; the foundation of astronautics."},
{"id": "aircraft_engine", "name": "Aircraft engine", "year": 1903, "cat": "aerospace", "wiki": "Aircraft engine", "req": ["internal_combustion_engine", "aluminium_smelting"], "desc": "A light, powerful piston engine built for flight; the Wrights' aluminium-block engine made powered flight possible."},
{"id": "wright_flyer", "name": "Wright Flyer", "year": 1903, "cat": "aerospace", "wiki": "Wright Flyer", "req": ["airplane", "wing_warping", "aircraft_engine", "aeronautical_propeller"], "desc": "The Wright brothers' biplane that made the first controlled, sustained powered flight on 17 December 1903."},
{"id": "pulsejet", "name": "Pulsejet", "year": 1906, "cat": "aerospace", "wiki": "Pulsejet", "req": ["internal_combustion_engine"], "desc": "A simple jet engine with intermittent combustion behind valves; later used in the V-1 flying bomb."},
{"id": "monoplane", "name": "Monoplane", "year": 1907, "cat": "aerospace", "wiki": "Monoplane", "req": ["airplane"], "desc": "An aircraft with a single main wing; Louis Blériot's monoplanes set the layout used by most later aircraft."},
{"id": "aileron", "name": "Aileron", "year": 1908, "cat": "aerospace", "wiki": "Aileron", "req": ["airplane"], "desc": "A hinged control surface at the wing's trailing edge for roll control; replaced wing warping."},
{"id": "rotary_engine", "name": "Rotary aircraft engine", "year": 1908, "cat": "aerospace", "wiki": "Rotary engine", "req": ["aircraft_engine"], "desc": "An air-cooled engine whose cylinders spin around a fixed crankshaft; the Gnome engine powered early aviation."},
{"id": "bleriot_xi", "name": "Blériot XI", "year": 1909, "cat": "aerospace", "wiki": "Blériot XI", "req": ["monoplane", "aircraft_engine"], "desc": "Louis Blériot's monoplane that made the first flight across the English Channel in 1909."},
{"id": "airport", "name": "Airport", "year": 1909, "cat": "aerospace", "wiki": "Airport", "req": ["airplane"], "desc": "A dedicated field with runways and services for aircraft; College Park, Maryland, opened in 1909."},
{"id": "seaplane", "name": "Seaplane", "year": 1910, "cat": "aerospace", "wiki": "Seaplane", "req": ["airplane"], "desc": "An aircraft that takes off from and lands on water; Henri Fabre flew the first in 1910."},
{"id": "monocoque", "name": "Monocoque fuselage", "year": 1912, "cat": "aerospace", "wiki": "Monocoque", "req": ["airplane"], "desc": "A fuselage whose skin carries the loads, introduced on the 1912 Deperdussin racer; led to stressed-skin aircraft."},
{"id": "autopilot", "name": "Autopilot", "year": 1912, "cat": "aerospace", "wiki": "Autopilot", "req": ["airplane", "electric_motor", "gyroscope"], "desc": "Lawrence Sperry's gyroscopic system that held an aircraft level and on course without pilot input."},
{"id": "airliner", "name": "Airliner", "year": 1913, "cat": "aerospace", "wiki": "Airliner", "req": ["airplane"], "desc": "A large aircraft for carrying passengers; Sikorsky's four-engine Russky Vityaz of 1913 pioneered the type."},
{"id": "junkers_j1", "name": "All-metal aircraft", "year": 1915, "cat": "aerospace", "wiki": "Junkers J 1", "req": ["airplane", "steel"], "desc": "Hugo Junkers's J 1, the first practical all-metal airplane, with an unbraced cantilever wing."},
{"id": "flap", "name": "Flap", "year": 1916, "cat": "aerospace", "wiki": "Flap (aeronautics)", "req": ["airfoil", "airplane"], "desc": "A hinged trailing-edge surface that raises lift at low speed, allowing slower takeoffs and landings."},
{"id": "uav", "name": "Unmanned aerial vehicle", "year": 1917, "cat": "aerospace", "wiki": "Unmanned aerial vehicle", "req": ["autopilot", "radio"], "desc": "An aircraft without a pilot aboard, flown by radio or autopilot; first built as aerial targets and flying bombs in 1917."},
{"id": "leading_edge_slat", "name": "Leading-edge slat", "year": 1919, "cat": "aerospace", "wiki": "Leading-edge slat", "req": ["airfoil", "wind_tunnel"], "desc": "A small airfoil ahead of the wing that delays stall; developed by Handley Page and Lachmann."},
{"id": "transatlantic_flight", "name": "First nonstop transatlantic flight", "year": 1919, "cat": "aerospace", "wiki": "Transatlantic flight of Alcock and Brown", "req": ["airplane", "aircraft_engine"], "desc": "John Alcock and Arthur Brown's 1919 nonstop flight from Newfoundland to Ireland, proving long overwater flight."},
{"id": "air_traffic_control", "name": "Air traffic control", "year": 1920, "cat": "aerospace", "wiki": "Air traffic control", "req": ["airport", "radio"], "desc": "Ground-based direction of aircraft to keep them separated; began at London's Croydon airport around 1920."},
{"id": "retractable_landing_gear", "name": "Retractable landing gear", "year": 1920, "cat": "aerospace", "wiki": "Landing gear", "req": ["airplane"], "desc": "Wheels that fold into the aircraft in flight to cut drag; adopted widely from the Dayton-Wright RB-1 onward."},
{"id": "aerial_application", "name": "Aerial application", "year": 1921, "cat": "aerospace", "wiki": "Aerial application", "req": ["airplane", "pesticide"], "desc": "Spraying crops with pesticides or fertilizer from aircraft; first done in Ohio in 1921."},
{"id": "quadcopter", "name": "Quadcopter", "year": 1922, "cat": "aerospace", "wiki": "Quadcopter", "req": ["aircraft_engine", "aeronautical_propeller"], "desc": "A rotorcraft lifted by four rotors; early crewed versions flew in 1922, and electronic stabilization made them common drones."},
{"id": "autogyro", "name": "Autogyro", "year": 1923, "cat": "aerospace", "wiki": "Autogyro", "req": ["airplane", "aeronautical_propeller"], "desc": "Juan de la Cierva's aircraft with a freely spinning rotor for lift; it introduced the hinged rotor blades used by helicopters."},
{"id": "aerial_refueling", "name": "Aerial refueling", "year": 1923, "cat": "aerospace", "wiki": "Aerial refueling", "req": ["airplane"], "desc": "Transferring fuel from one aircraft to another in flight to extend range; first done by the US Army in 1923."},
{"id": "variable_pitch_propeller", "name": "Variable-pitch propeller", "year": 1924, "cat": "aerospace", "wiki": "Variable-pitch propeller (aeronautics)", "req": ["aeronautical_propeller"], "desc": "A propeller whose blade angle can change in flight for efficient takeoff and cruise."},
{"id": "hohmann_transfer", "name": "Hohmann transfer orbit", "year": 1925, "cat": "aerospace", "wiki": "Hohmann transfer orbit", "req": ["classical_mechanics"], "desc": "Walter Hohmann's fuel-efficient two-burn path between orbits, the basis of interplanetary mission design."},
{"id": "flight_simulator", "name": "Flight simulator", "year": 1929, "cat": "aerospace", "wiki": "Flight simulator", "req": ["airplane"], "desc": "A ground device that reproduces flight for pilot training; Edwin Link's 1929 trainer was the first practical one."},
{"id": "attitude_indicator", "name": "Attitude indicator", "year": 1929, "cat": "aerospace", "wiki": "Attitude indicator", "req": ["autopilot", "gyroscope"], "desc": "A gyroscopic artificial horizon that let pilots fly in cloud; key to Jimmy Doolittle's 1929 blind flight."},
{"id": "delta_wing", "name": "Delta wing", "year": 1931, "cat": "aerospace", "wiki": "Delta wing", "req": ["glider", "wind_tunnel"], "desc": "A triangular wing, pioneered by Alexander Lippisch's gliders, suited to supersonic flight."},
{"id": "high_altitude_balloon", "name": "High-altitude balloon", "year": 1931, "cat": "aerospace", "wiki": "High-altitude balloon", "req": ["gas_balloon", "aluminium_smelting"], "desc": "Auguste Piccard's balloon with a sealed gondola that carried people into the stratosphere in 1931."},
{"id": "hybrid_rocket", "name": "Hybrid-propellant rocket", "year": 1933, "cat": "aerospace", "wiki": "Hybrid-propellant rocket", "req": ["liquid_rocket"], "desc": "A rocket burning a liquid oxidizer with a solid fuel; the Soviet GIRD-09 flew in 1933."},
{"id": "pressure_suit", "name": "Pressure suit", "year": 1934, "cat": "aerospace", "wiki": "Pressure suit", "req": ["vulcanization", "airplane"], "desc": "A sealed suit that keeps its wearer pressurized at high altitude; Wiley Post flew in one in 1934."},
{"id": "douglas_dc3", "name": "Douglas DC-3", "year": 1935, "cat": "aerospace", "wiki": "Douglas DC-3", "req": ["airliner", "retractable_landing_gear", "variable_pitch_propeller", "monocoque"], "desc": "The all-metal airliner that made passenger air travel profitable and became the most widely used transport aircraft."},
{"id": "helicopter", "name": "Helicopter", "year": 1936, "cat": "aerospace", "wiki": "Helicopter", "req": ["autogyro", "aircraft_engine"], "desc": "A rotorcraft that lifts and steers with powered rotors; the Focke-Wulf Fw 61 of 1936 was the first fully controllable one."},
{"id": "cabin_pressurization", "name": "Pressurized cabin", "year": 1937, "cat": "aerospace", "wiki": "Cabin pressurization", "req": ["monocoque", "airliner"], "desc": "Pumping air into a sealed fuselage so aircraft can fly above the weather; first on the Lockheed XC-35."},
{"id": "instrument_landing_system", "name": "Instrument landing system", "year": 1938, "cat": "aerospace", "wiki": "Instrument landing system", "req": ["radio", "airport"], "desc": "Radio beams that guide aircraft down to the runway in poor visibility."},
{"id": "turbojet", "name": "Turbojet", "year": 1939, "cat": "aerospace", "wiki": "Turbojet", "req": ["jet_engine"], "desc": "A jet engine whose entire thrust comes from exhaust; the Heinkel He 178 made the first jet-powered flight in 1939."},
{"id": "ramjet", "name": "Ramjet", "year": 1939, "cat": "aerospace", "wiki": "Ramjet", "req": ["aerodynamics", "thermodynamics"], "desc": "A jet engine with no moving parts that compresses air by forward speed alone; first flight-tested in the USSR in 1939."},
{"id": "inertial_navigation", "name": "Inertial navigation system", "year": 1942, "cat": "aerospace", "wiki": "Inertial navigation system", "req": ["autopilot", "gyroscope", "accelerometer"], "desc": "Gyroscopes and accelerometers that track position without outside references; first used to guide the V-2."},
{"id": "composite_propellant", "name": "Composite solid propellant", "year": 1942, "cat": "aerospace", "wiki": "Ammonium perchlorate composite propellant", "req": ["rocket"], "desc": "Oxidizer crystals bound in a rubbery fuel, developed at GALCIT; the basis of large modern solid rocket motors."},
{"id": "turbopump", "name": "Turbopump", "year": 1942, "cat": "aerospace", "wiki": "Turbopump", "req": ["liquid_rocket", "gas_turbine"], "desc": "A turbine-driven pump that feeds propellant into a rocket engine at high pressure; made large liquid rockets possible."},
{"id": "v2_rocket", "name": "V-2 rocket", "year": 1942, "cat": "aerospace", "wiki": "V-2 rocket", "req": ["liquid_rocket", "turbopump", "inertial_navigation", "de_laval_nozzle"], "desc": "The first large guided liquid-fuel rocket and the first object to reach space, in 1944; it seeded postwar rocketry."},
{"id": "ejection_seat", "name": "Ejection seat", "year": 1942, "cat": "aerospace", "wiki": "Ejection seat", "req": ["parachute", "airplane"], "desc": "A seat that fires the pilot clear of a disabled aircraft before a parachute opens."},
{"id": "sikorsky_r4", "name": "Sikorsky R-4", "year": 1942, "cat": "aerospace", "wiki": "Sikorsky R-4", "req": ["helicopter"], "desc": "The first helicopter built in quantity, using Igor Sikorsky's single main rotor and tail rotor layout."},
{"id": "afterburner", "name": "Afterburner", "year": 1944, "cat": "aerospace", "wiki": "Afterburner", "req": ["turbojet"], "desc": "Extra fuel burned in a jet's exhaust for a short burst of thrust; used by supersonic aircraft."},
{"id": "turboprop", "name": "Turboprop", "year": 1945, "cat": "aerospace", "wiki": "Turboprop", "req": ["turbojet", "aeronautical_propeller"], "desc": "A gas turbine driving a propeller, efficient at medium speeds; first flown on the Gloster Trent Meteor."},
{"id": "sounding_rocket", "name": "Sounding rocket", "year": 1945, "cat": "aerospace", "wiki": "Sounding rocket", "req": ["liquid_rocket"], "desc": "A research rocket that carries instruments on a brief suborbital flight; the WAC Corporal was an early example."},
{"id": "vor", "name": "VHF omnidirectional range", "year": 1946, "cat": "aerospace", "wiki": "VHF omnidirectional range", "req": ["radio", "air_traffic_control"], "desc": "Ground radio beacons that give aircraft their bearing, forming the airway network for decades."},
{"id": "swept_wing", "name": "Swept wing", "year": 1947, "cat": "aerospace", "wiki": "Swept wing", "req": ["turbojet", "wind_tunnel"], "desc": "A wing angled back to delay shock waves near the speed of sound, standard on jet aircraft."},
{"id": "bell_x1", "name": "Bell X-1", "year": 1947, "cat": "aerospace", "wiki": "Bell X-1", "req": ["liquid_rocket", "airplane", "wind_tunnel"], "desc": "The rocket plane in which Chuck Yeager made the first supersonic level flight in 1947."},
{"id": "animals_in_space", "name": "Animals in space", "year": 1947, "cat": "aerospace", "wiki": "Animals in space", "req": ["v2_rocket"], "desc": "Fruit flies, monkeys and dogs flown on rockets to test whether living things could survive spaceflight."},
{"id": "rogallo_wing", "name": "Rogallo wing", "year": 1948, "cat": "aerospace", "wiki": "Rogallo wing", "req": ["kite"], "desc": "Francis Rogallo's flexible fabric wing, which led to the modern hang glider."},
{"id": "multistage_rocket", "name": "Multistage rocket", "year": 1949, "cat": "aerospace", "wiki": "Multistage rocket", "req": ["v2_rocket", "sounding_rocket"], "desc": "A rocket that drops spent stages to reach higher speeds; Bumper, a V-2 with a WAC Corporal upper stage, flew in 1949."},
{"id": "jet_airliner", "name": "Jet airliner", "year": 1949, "cat": "aerospace", "wiki": "Jet airliner", "req": ["turbojet", "cabin_pressurization", "airliner"], "desc": "A passenger aircraft powered by jet engines; the de Havilland Comet first flew in 1949 and halved travel times."},
{"id": "turboshaft", "name": "Turboshaft", "year": 1951, "cat": "aerospace", "wiki": "Turboshaft", "req": ["gas_turbine", "helicopter"], "desc": "A gas turbine built to drive a shaft rather than make thrust; it transformed helicopter power and payload."},
{"id": "variable_sweep_wing", "name": "Variable-sweep wing", "year": 1951, "cat": "aerospace", "wiki": "Variable-sweep wing", "req": ["swept_wing"], "desc": "A wing that pivots to change sweep in flight, first flown on the Bell X-5 in 1951."},
{"id": "area_rule", "name": "Area rule", "year": 1952, "cat": "aerospace", "wiki": "Area rule", "req": ["wind_tunnel", "bell_x1"], "desc": "Richard Whitcomb's rule for shaping aircraft to cut drag near the speed of sound."},
{"id": "vtol", "name": "VTOL aircraft", "year": 1954, "cat": "aerospace", "wiki": "V/STOL", "req": ["turbojet", "helicopter"], "desc": "Fixed-wing aircraft that take off and land vertically, using jet lift or tilting rotors; later the Harrier."},
{"id": "tiltrotor", "name": "Tiltrotor", "year": 1955, "cat": "aerospace", "wiki": "Tiltrotor", "req": ["helicopter", "vtol"], "desc": "An aircraft with rotors that tilt from vertical lift to forward flight; the Bell XV-3 first converted in 1958."},
{"id": "boeing_707", "name": "Boeing 707", "year": 1957, "cat": "aerospace", "wiki": "Boeing 707", "req": ["jet_airliner", "swept_wing"], "desc": "The swept-wing jet airliner that began the jet age of mass air travel."},
{"id": "flight_recorder", "name": "Flight recorder", "year": 1957, "cat": "aerospace", "wiki": "Flight recorder", "req": ["jet_airliner"], "desc": "A crash-proof recorder of flight data and cockpit sounds, devised by David Warren after Comet accidents."},
{"id": "r7_rocket", "name": "R-7 rocket", "year": 1957, "cat": "aerospace", "wiki": "R-7 (rocket family)", "req": ["multistage_rocket", "rocket_equation"], "desc": "Sergei Korolev's rocket with strap-on boosters, the first ICBM and launcher of Sputnik, Vostok and Soyuz."},
{"id": "sputnik_1", "name": "Sputnik 1", "year": 1957, "cat": "aerospace", "wiki": "Sputnik 1", "req": ["satellite", "r7_rocket", "radio"], "desc": "The first artificial satellite, launched by the USSR on 4 October 1957, which began the Space Age."},
{"id": "atmospheric_entry", "name": "Atmospheric entry heat shield", "year": 1957, "cat": "aerospace", "wiki": "Atmospheric entry", "req": ["multistage_rocket"], "desc": "Blunt and ablative heat shields that let a vehicle survive returning through the atmosphere from space."},
{"id": "spacecraft_solar_panels", "name": "Spacecraft solar panels", "year": 1958, "cat": "aerospace", "wiki": "Solar panels on spacecraft", "req": ["solar_cell", "satellite"], "desc": "Solar cells powering spacecraft, first on Vanguard 1; they let satellites run for years."},
{"id": "communications_satellite", "name": "Communications satellite", "year": 1958, "cat": "aerospace", "wiki": "Communications satellite", "req": ["satellite", "radio"], "desc": "A satellite that relays radio, TV and phone signals; SCORE in 1958 and Telstar in 1962 were early ones."},
{"id": "explorer_1", "name": "Explorer 1", "year": 1958, "cat": "aerospace", "wiki": "Explorer 1", "req": ["satellite", "multistage_rocket", "geiger_counter"], "desc": "The first US satellite, which discovered the Van Allen radiation belts."},
{"id": "head_up_display", "name": "Head-up display", "year": 1958, "cat": "aerospace", "wiki": "Head-up display", "req": ["cathode_ray_tube", "attitude_indicator"], "desc": "A transparent display that projects flight data into the pilot's view."},
{"id": "x15", "name": "North American X-15", "year": 1959, "cat": "aerospace", "wiki": "North American X-15", "req": ["bell_x1", "liquid_rocket", "superalloy"], "desc": "A rocket plane that reached Mach 6.7 and the edge of space, testing hypersonic flight and reaction controls."},
{"id": "space_probe", "name": "Space probe", "year": 1959, "cat": "aerospace", "wiki": "Space probe", "req": ["r7_rocket", "satellite"], "desc": "An uncrewed spacecraft sent beyond Earth orbit; Luna 1, 2 and 3 reached the Moon in 1959."},
{"id": "gravity_assist", "name": "Gravity assist", "year": 1959, "cat": "aerospace", "wiki": "Gravity assist", "req": ["space_probe", "hohmann_transfer"], "desc": "Using a planet's gravity to change a probe's speed and path; first used by Luna 3 in 1959."},
{"id": "nuclear_thermal_rocket", "name": "Nuclear thermal rocket", "year": 1959, "cat": "aerospace", "wiki": "Nuclear thermal rocket", "req": ["nuclear_reactor", "liquid_rocket"], "desc": "A rocket that heats hydrogen in a fission reactor; ground-tested in the Kiwi and NERVA programs."},
{"id": "weather_satellite", "name": "Weather satellite", "year": 1960, "cat": "aerospace", "wiki": "Weather satellite", "req": ["satellite", "television"], "desc": "A satellite that images clouds and measures the atmosphere; TIROS-1 sent the first TV pictures of weather in 1960."},
{"id": "transit_satellite", "name": "Transit navigation satellite", "year": 1960, "cat": "aerospace", "wiki": "Transit (satellite navigation system)", "req": ["satellite", "radio", "doppler_effect"], "desc": "The first satellite navigation system, using Doppler shift to fix positions of ships and submarines."},
{"id": "earth_observation_satellite", "name": "Earth observation satellite", "year": 1960, "cat": "aerospace", "wiki": "Earth observation satellite", "req": ["satellite", "photography", "atmospheric_entry"], "desc": "A satellite that images Earth's surface; the Corona spy satellites first returned film from orbit in 1960."},
{"id": "space_capsule", "name": "Space capsule", "year": 1960, "cat": "aerospace", "wiki": "Space capsule", "req": ["atmospheric_entry", "parachute", "satellite"], "desc": "A blunt crewed or animal-carrying spacecraft that returns by heat shield and parachute; first recovered in 1960."},
{"id": "turbofan", "name": "Turbofan", "year": 1960, "cat": "aerospace", "wiki": "Turbofan", "req": ["turbojet"], "desc": "A jet engine that drives a large fan to push extra air around the core, quieter and more efficient than a turbojet."},
{"id": "space_suit", "name": "Space suit", "year": 1961, "cat": "aerospace", "wiki": "Space suit", "req": ["pressure_suit"], "desc": "A pressurized garment that keeps astronauts alive in vacuum; first worn by Yuri Gagarin."},
{"id": "vostok_1", "name": "Vostok 1", "year": 1961, "cat": "aerospace", "wiki": "Vostok 1", "req": ["space_capsule", "space_suit", "r7_rocket"], "desc": "The flight that made Yuri Gagarin the first human in space and in orbit, on 12 April 1961."},
{"id": "rtg", "name": "Radioisotope thermoelectric generator", "year": 1961, "cat": "aerospace", "wiki": "Radioisotope thermoelectric generator", "req": ["satellite", "semiconductor", "thermoelectric_effect", "nuclear_reactor"], "desc": "A generator that turns heat from radioactive decay into electricity, powering probes far from the Sun."},
{"id": "staged_combustion", "name": "Staged combustion cycle", "year": 1961, "cat": "aerospace", "wiki": "Staged combustion cycle", "req": ["turbopump"], "desc": "A rocket engine cycle that burns turbine exhaust in the main chamber for high efficiency; pioneered in the USSR."},
{"id": "human_powered_aircraft", "name": "Human-powered aircraft", "year": 1961, "cat": "aerospace", "wiki": "Human-powered aircraft", "req": ["glider"], "desc": "An aircraft flown by the pilot's muscle power; the Gossamer Albatross crossed the English Channel in 1979."},
{"id": "jet_pack", "name": "Jet pack", "year": 1961, "cat": "aerospace", "wiki": "Jet pack", "req": ["liquid_rocket"], "desc": "A backpack thruster for individual flight; the Bell Rocket Belt first flew freely in 1961."},
{"id": "project_mercury", "name": "Project Mercury", "year": 1961, "cat": "aerospace", "wiki": "Project Mercury", "req": ["space_capsule", "space_suit"], "desc": "The first US human spaceflight program; Alan Shepard flew in 1961 and John Glenn orbited in 1962."},
{"id": "mariner_2", "name": "Mariner 2", "year": 1962, "cat": "aerospace", "wiki": "Mariner 2", "req": ["space_probe", "spacecraft_solar_panels"], "desc": "The first successful planetary flyby, passing Venus in 1962."},
{"id": "cryogenic_rocket_engine", "name": "Cryogenic rocket engine", "year": 1963, "cat": "aerospace", "wiki": "Cryogenic rocket engine", "req": ["liquid_rocket", "turbopump", "liquefaction_of_gases"], "desc": "An engine burning liquid hydrogen and oxygen for the highest chemical efficiency; the RL10 first flew in 1963."},
{"id": "deep_space_network", "name": "Deep Space Network", "year": 1963, "cat": "aerospace", "wiki": "NASA Deep Space Network", "req": ["space_probe", "radio"], "desc": "A worldwide array of large antennas that tracks and talks to distant spacecraft."},
{"id": "geostationary_satellite", "name": "Geostationary satellite", "year": 1964, "cat": "aerospace", "wiki": "Geostationary orbit", "req": ["communications_satellite", "hohmann_transfer"], "desc": "A satellite that orbits in step with Earth's rotation and appears fixed in the sky; Syncom 3 was the first."},
{"id": "ion_thruster", "name": "Ion thruster", "year": 1964, "cat": "aerospace", "wiki": "Ion thruster", "req": ["satellite", "electromagnetism"], "desc": "An engine that accelerates ions electrically for very efficient, low thrust; tested on SERT-1 in 1964."},
{"id": "high_bypass_turbofan", "name": "High-bypass turbofan", "year": 1964, "cat": "aerospace", "wiki": "General Electric TF39", "req": ["turbofan"], "desc": "The GE TF39, first high-bypass turbofan, which made wide-body aircraft economical."},
{"id": "parafoil", "name": "Parafoil", "year": 1964, "cat": "aerospace", "wiki": "Parafoil", "req": ["parachute", "kite"], "desc": "Domina Jalbert's ram-air inflated fabric wing, the basis of steerable parachutes and paragliders."},
{"id": "eva", "name": "Extravehicular activity", "year": 1965, "cat": "aerospace", "wiki": "Extravehicular activity", "req": ["space_suit", "space_capsule"], "desc": "Working outside a spacecraft in a space suit; Alexei Leonov made the first spacewalk in 1965."},
{"id": "space_rendezvous", "name": "Space rendezvous", "year": 1965, "cat": "aerospace", "wiki": "Space rendezvous", "req": ["space_capsule", "hohmann_transfer", "radar"], "desc": "Bringing two spacecraft together in orbit, first done by Gemini 6A and 7 in 1965."},
{"id": "mariner_4", "name": "Mariner 4", "year": 1965, "cat": "aerospace", "wiki": "Mariner 4", "req": ["space_probe", "spacecraft_solar_panels", "television"], "desc": "The first successful flyby of Mars, returning the first close-up pictures of another planet."},
{"id": "spacecraft_docking", "name": "Spacecraft docking", "year": 1966, "cat": "aerospace", "wiki": "Docking and berthing of spacecraft", "req": ["space_rendezvous"], "desc": "Physically joining two spacecraft in orbit, first done by Gemini 8 with an Agena target in 1966."},
{"id": "luna_9", "name": "Luna 9", "year": 1966, "cat": "aerospace", "wiki": "Luna 9", "req": ["space_probe", "television"], "desc": "The first spacecraft to soft-land on the Moon and send pictures from its surface."},
{"id": "apollo_guidance_computer", "name": "Apollo Guidance Computer", "year": 1966, "cat": "aerospace", "wiki": "Apollo Guidance Computer", "req": ["integrated_circuit", "inertial_navigation", "magnetic_core_memory"], "desc": "The compact integrated-circuit computer that navigated the Apollo spacecraft to the Moon."},
{"id": "soyuz", "name": "Soyuz spacecraft", "year": 1967, "cat": "aerospace", "wiki": "Soyuz (spacecraft)", "req": ["space_capsule", "spacecraft_docking", "r7_rocket"], "desc": "A three-person Soviet spacecraft, still flying, which became the longest-serving crewed vehicle."},
{"id": "saturn_v", "name": "Saturn V", "year": 1967, "cat": "aerospace", "wiki": "Saturn V", "req": ["multistage_rocket", "cryogenic_rocket_engine", "turbopump"], "desc": "The three-stage super heavy rocket that launched the Apollo Moon missions."},
{"id": "apollo_lunar_module", "name": "Apollo Lunar Module", "year": 1968, "cat": "aerospace", "wiki": "Apollo Lunar Module", "req": ["apollo_guidance_computer", "spacecraft_docking"], "desc": "The two-stage lander that carried astronauts from lunar orbit to the surface and back."},
{"id": "space_telescope", "name": "Space telescope", "year": 1968, "cat": "aerospace", "wiki": "Space telescope", "req": ["satellite", "telescope"], "desc": "A telescope in orbit, above the blurring and absorbing atmosphere; OAO-2 was the first successful one."},
{"id": "supersonic_transport", "name": "Supersonic transport", "year": 1968, "cat": "aerospace", "wiki": "Supersonic transport", "req": ["jet_airliner", "delta_wing", "afterburner", "area_rule"], "desc": "An airliner that cruises faster than sound; the Tupolev Tu-144 flew first, in 1968."},
{"id": "apollo_8", "name": "Apollo 8", "year": 1968, "cat": "aerospace", "wiki": "Apollo 8", "req": ["saturn_v", "apollo_guidance_computer"], "desc": "The first crewed spacecraft to leave Earth orbit and circle the Moon, in December 1968."},
{"id": "apollo_11", "name": "Apollo 11 Moon landing", "year": 1969, "cat": "aerospace", "wiki": "Apollo 11", "req": ["saturn_v", "apollo_lunar_module", "eva", "luna_9"], "desc": "The mission that landed Neil Armstrong and Buzz Aldrin on the Moon on 20 July 1969."},
{"id": "concorde", "name": "Concorde", "year": 1969, "cat": "aerospace", "wiki": "Concorde", "req": ["supersonic_transport"], "desc": "The Anglo-French supersonic airliner that crossed the Atlantic in under 3.5 hours from 1976 to 2003."},
{"id": "wide_body", "name": "Wide-body aircraft", "year": 1969, "cat": "aerospace", "wiki": "Wide-body aircraft", "req": ["high_bypass_turbofan", "jet_airliner"], "desc": "A twin-aisle airliner that cut the cost per seat and opened long-haul flying to mass travel."},
{"id": "boeing_747", "name": "Boeing 747", "year": 1969, "cat": "aerospace", "wiki": "Boeing 747", "req": ["wide_body"], "desc": "The first wide-body jumbo jet, which dominated long-haul air travel for decades."},
{"id": "venera_7", "name": "Venera 7", "year": 1970, "cat": "aerospace", "wiki": "Venera 7", "req": ["space_probe", "atmospheric_entry"], "desc": "The first spacecraft to land on another planet, Venus, and transmit data from its surface."},
{"id": "lunokhod_1", "name": "Lunokhod 1", "year": 1970, "cat": "aerospace", "wiki": "Lunokhod 1", "req": ["luna_9"], "desc": "The first robotic rover on another world, driven remotely across the Moon."},
{"id": "sample_return", "name": "Sample return mission", "year": 1970, "cat": "aerospace", "wiki": "Sample-return mission", "req": ["luna_9", "atmospheric_entry"], "desc": "A robotic mission that brings material back to Earth; Luna 16 returned lunar soil in 1970."},
{"id": "salyut", "name": "Salyut space station", "year": 1971, "cat": "aerospace", "wiki": "Salyut programme", "req": ["soyuz", "spacecraft_docking"], "desc": "The Soviet Salyut 1, the first space station, followed by a series of long-duration orbital outposts."},
{"id": "hall_thruster", "name": "Hall-effect thruster", "year": 1971, "cat": "aerospace", "wiki": "Hall-effect thruster", "req": ["ion_thruster"], "desc": "An electric thruster that traps electrons in a magnetic field to ionize propellant; common on modern satellites."},
{"id": "supercritical_airfoil", "name": "Supercritical airfoil", "year": 1971, "cat": "aerospace", "wiki": "Supercritical airfoil", "req": ["airfoil", "wind_tunnel"], "desc": "A flattened wing section by Richard Whitcomb that delays drag rise near the speed of sound."},
{"id": "lunar_roving_vehicle", "name": "Lunar Roving Vehicle", "year": 1971, "cat": "aerospace", "wiki": "Lunar Roving Vehicle", "req": ["apollo_11", "electric_motor"], "desc": "A battery-powered car driven by astronauts on the Moon during the last three Apollo missions."},
{"id": "mariner_9", "name": "Mariner 9", "year": 1971, "cat": "aerospace", "wiki": "Mariner 9", "req": ["mariner_4"], "desc": "The first spacecraft to orbit another planet, mapping Mars in 1971 and 1972."},
{"id": "pioneer_10", "name": "Pioneer 10", "year": 1972, "cat": "aerospace", "wiki": "Pioneer 10", "req": ["space_probe", "rtg", "gravity_assist"], "desc": "The first probe to cross the asteroid belt and fly past Jupiter."},
{"id": "landsat", "name": "Landsat", "year": 1972, "cat": "aerospace", "wiki": "Landsat program", "req": ["earth_observation_satellite"], "desc": "The longest-running civilian Earth imaging program, mapping land use, crops and forests since 1972."},
{"id": "fly_by_wire", "name": "Fly-by-wire", "year": 1972, "cat": "aerospace", "wiki": "Fly-by-wire", "req": ["autopilot", "electronic_computer", "integrated_circuit"], "desc": "Flight controls run by computers and wires instead of cables; NASA's F-8 first flew digital fly-by-wire in 1972."},
{"id": "electric_aircraft", "name": "Electric aircraft", "year": 1973, "cat": "aerospace", "wiki": "Electric aircraft", "req": ["electric_motor", "glider"], "desc": "An aircraft driven by electric motors; the battery-powered MB-E1 made the first crewed electric flight in 1973."},
{"id": "skylab", "name": "Skylab", "year": 1973, "cat": "aerospace", "wiki": "Skylab", "req": ["saturn_v", "salyut"], "desc": "The first US space station, built from a Saturn V stage, which hosted three crews in 1973 and 1974."},
{"id": "gpws", "name": "Ground proximity warning system", "year": 1974, "cat": "aerospace", "wiki": "Ground proximity warning system", "req": ["radar", "radio"], "desc": "A system that warns pilots when an aircraft is in danger of flying into terrain."},
{"id": "viking_program", "name": "Viking Mars landers", "year": 1976, "cat": "aerospace", "wiki": "Viking program", "req": ["space_probe", "atmospheric_entry", "rtg"], "desc": "The first fully successful landings on Mars, which studied its surface and searched for life."},
{"id": "voyager", "name": "Voyager program", "year": 1977, "cat": "aerospace", "wiki": "Voyager program", "req": ["gravity_assist", "rtg", "deep_space_network"], "desc": "Two probes that toured the outer planets; Voyager 1 entered interstellar space in 2012."},
{"id": "stealth_aircraft", "name": "Stealth aircraft", "year": 1977, "cat": "aerospace", "wiki": "Stealth aircraft", "req": ["radar", "fly_by_wire", "electronic_computer", "bomber"], "desc": "Aircraft shaped and coated to be hard to detect by radar, first demonstrated by Have Blue in 1977."},
{"id": "gps", "name": "Global Positioning System", "year": 1978, "cat": "aerospace", "wiki": "Global Positioning System", "req": ["transit_satellite", "integrated_circuit", "atomic_clock"], "desc": "A constellation of satellites broadcasting precise time signals so receivers anywhere can find their position."},
{"id": "progress_spacecraft", "name": "Progress cargo spacecraft", "year": 1978, "cat": "aerospace", "wiki": "Progress (spacecraft)", "req": ["soyuz", "salyut"], "desc": "An uncrewed automated freighter that resupplies space stations, enabling long-duration crews."},
{"id": "wingtip_device", "name": "Winglet", "year": 1979, "cat": "aerospace", "wiki": "Wingtip device", "req": ["supercritical_airfoil"], "desc": "Upturned wingtips that reduce induced drag and fuel burn, flight-tested by NASA in 1979."},
{"id": "space_shuttle", "name": "Space Shuttle", "year": 1981, "cat": "aerospace", "wiki": "Space Shuttle", "req": ["cryogenic_rocket_engine", "staged_combustion", "composite_propellant", "atmospheric_entry", "carbon_carbon", "fly_by_wire"], "desc": "NASA's partly reusable winged orbiter, which flew 135 missions from 1981 to 2011."},
{"id": "canadarm", "name": "Canadarm", "year": 1981, "cat": "aerospace", "wiki": "Canadarm", "req": ["space_shuttle"], "desc": "A robotic arm on the Space Shuttle for deploying and capturing payloads."},
{"id": "glass_cockpit", "name": "Glass cockpit", "year": 1982, "cat": "aerospace", "wiki": "Glass cockpit", "req": ["cathode_ray_tube", "microprocessor"], "desc": "Electronic screens replacing mechanical cockpit gauges, first on the Boeing 767 and Airbus A310."},
{"id": "glonass", "name": "GLONASS", "year": 1982, "cat": "aerospace", "wiki": "GLONASS", "req": ["transit_satellite", "integrated_circuit", "atomic_clock"], "desc": "Russia's global satellite navigation system, the second fully global one after GPS."},
{"id": "mir", "name": "Mir", "year": 1986, "cat": "aerospace", "wiki": "Mir", "req": ["salyut", "progress_spacecraft"], "desc": "The first modular space station, assembled in orbit and crewed almost continuously for ten years."},
{"id": "airbus_a320", "name": "Airbus A320", "year": 1987, "cat": "aerospace", "wiki": "Airbus A320 family", "req": ["fly_by_wire", "glass_cockpit", "turbofan"], "desc": "The first airliner with digital fly-by-wire and side-stick controls, and one of the best-selling jets."},
{"id": "buran", "name": "Buran", "year": 1988, "cat": "aerospace", "wiki": "Buran (spacecraft)", "req": ["space_shuttle"], "desc": "The Soviet reusable orbiter that made a single uncrewed orbital flight and automatic landing in 1988."},
{"id": "hubble", "name": "Hubble Space Telescope", "year": 1990, "cat": "aerospace", "wiki": "Hubble Space Telescope", "req": ["space_telescope", "space_shuttle", "ccd"], "desc": "A large optical telescope in orbit, serviced by astronauts, that reshaped astronomy."},
{"id": "tcas", "name": "Traffic collision avoidance system", "year": 1990, "cat": "aerospace", "wiki": "Traffic collision avoidance system", "req": ["air_traffic_control", "microprocessor"], "desc": "An onboard system that interrogates nearby transponders and tells pilots how to avoid mid-air collisions."},
{"id": "scramjet", "name": "Scramjet", "year": 1991, "cat": "aerospace", "wiki": "Scramjet", "req": ["ramjet"], "desc": "A ramjet with supersonic airflow through the combustor, for hypersonic flight; first flight-tested in 1991."},
{"id": "vtvl", "name": "Vertical landing rocket", "year": 1993, "cat": "aerospace", "wiki": "VTVL", "req": ["liquid_rocket", "fly_by_wire"], "desc": "Rockets that take off and land vertically on their engines; the DC-X demonstrated it in 1993."},
{"id": "galileo_probe", "name": "Galileo spacecraft", "year": 1995, "cat": "aerospace", "wiki": "Galileo (spacecraft)", "req": ["gravity_assist", "rtg", "atmospheric_entry"], "desc": "The first spacecraft to orbit Jupiter, which also dropped a probe into its atmosphere in 1995."},
{"id": "mars_rover", "name": "Mars rover", "year": 1997, "cat": "aerospace", "wiki": "Mars rover", "req": ["lunokhod_1", "viking_program"], "desc": "A robotic vehicle that drives across Mars; Sojourner was the first to operate there, in 1997."},
{"id": "iss", "name": "International Space Station", "year": 1998, "cat": "aerospace", "wiki": "International Space Station", "req": ["mir", "space_shuttle", "canadarm"], "desc": "A multinational modular station, continuously crewed since 2000, the largest structure in orbit."},
{"id": "iridium", "name": "Iridium satellite constellation", "year": 1998, "cat": "aerospace", "wiki": "Iridium satellite constellation", "req": ["communications_satellite", "mobile_phone"], "desc": "A network of 66 low-orbit satellites giving phone coverage everywhere on Earth."},
{"id": "chandra", "name": "Chandra X-ray Observatory", "year": 1999, "cat": "aerospace", "wiki": "Chandra X-ray Observatory", "req": ["space_telescope", "space_shuttle", "ccd"], "desc": "A space telescope with nested grazing-incidence mirrors that images the X-ray sky in fine detail."},
{"id": "beidou", "name": "BeiDou", "year": 2000, "cat": "aerospace", "wiki": "BeiDou", "req": ["gps"], "desc": "China's satellite navigation system, regional from 2000 and global from 2020."},
{"id": "space_tourism", "name": "Space tourism", "year": 2001, "cat": "aerospace", "wiki": "Space tourism", "req": ["iss", "soyuz"], "desc": "Paid private travel to space, beginning with Dennis Tito's visit to the ISS in 2001."},
{"id": "cubesat", "name": "CubeSat", "year": 2003, "cat": "aerospace", "wiki": "CubeSat", "req": ["satellite", "microprocessor"], "desc": "A standard satellite built from 10 cm cubes, which made spaceflight affordable for universities and startups."},
{"id": "shenzhou_5", "name": "Shenzhou 5", "year": 2003, "cat": "aerospace", "wiki": "Shenzhou 5", "req": ["space_capsule", "space_suit"], "desc": "China's first crewed spaceflight, carrying Yang Liwei to orbit in 2003."},
{"id": "spaceshipone", "name": "SpaceShipOne", "year": 2004, "cat": "aerospace", "wiki": "SpaceShipOne", "req": ["hybrid_rocket", "x15"], "desc": "The first privately developed crewed spacecraft to reach space, winning the Ansari X Prize in 2004."},
{"id": "cassini_huygens", "name": "Cassini-Huygens", "year": 2004, "cat": "aerospace", "wiki": "Cassini–Huygens", "req": ["voyager", "rtg"], "desc": "A mission that orbited Saturn for 13 years and landed the Huygens probe on Titan in 2005."},
{"id": "x43", "name": "NASA X-43", "year": 2004, "cat": "aerospace", "wiki": "NASA X-43", "req": ["scramjet"], "desc": "An uncrewed scramjet test vehicle that reached Mach 9.6 in 2004, the fastest air-breathing flight."},
{"id": "airbus_a380", "name": "Airbus A380", "year": 2005, "cat": "aerospace", "wiki": "Airbus A380", "req": ["wide_body", "fly_by_wire", "cfrp"], "desc": "A full-length double-deck airliner, the largest passenger aircraft ever built."},
{"id": "boeing_787", "name": "Boeing 787 Dreamliner", "year": 2009, "cat": "aerospace", "wiki": "Boeing 787 Dreamliner", "req": ["wide_body", "fly_by_wire", "cfrp"], "desc": "The first airliner with a mostly carbon-fiber composite airframe, cutting weight and fuel use."},
{"id": "solar_impulse", "name": "Solar Impulse", "year": 2009, "cat": "aerospace", "wiki": "Solar Impulse", "req": ["electric_aircraft", "solar_cell", "lithium_ion_battery"], "desc": "A solar-electric aircraft that flew around the world without fuel in 2015 and 2016."},
{"id": "kepler_telescope", "name": "Kepler space telescope", "year": 2009, "cat": "aerospace", "wiki": "Kepler space telescope", "req": ["space_telescope", "ccd"], "desc": "A space telescope that found thousands of exoplanets by watching stars dim as planets crossed them."},
{"id": "falcon_9", "name": "Falcon 9", "year": 2010, "cat": "aerospace", "wiki": "Falcon 9", "req": ["multistage_rocket", "gps", "liquid_rocket", "turbopump"], "desc": "SpaceX's two-stage medium-lift rocket, which became the most-flown launcher in the world."},
{"id": "hayabusa", "name": "Hayabusa", "year": 2010, "cat": "aerospace", "wiki": "Hayabusa", "req": ["sample_return", "ion_thruster"], "desc": "A Japanese ion-propelled probe that returned the first samples from an asteroid in 2010."},
{"id": "solar_sail", "name": "Solar sail", "year": 2010, "cat": "aerospace", "wiki": "Solar sail", "req": ["space_probe"], "desc": "A large thin sail pushed by sunlight; Japan's IKAROS first demonstrated it between planets in 2010."},
{"id": "spacex_dragon", "name": "SpaceX Dragon", "year": 2010, "cat": "aerospace", "wiki": "SpaceX Dragon 1", "req": ["space_capsule", "falcon_9"], "desc": "The first commercial spacecraft recovered from orbit, later the first to deliver cargo to the ISS."},
{"id": "evtol", "name": "eVTOL aircraft", "year": 2011, "cat": "aerospace", "wiki": "EVTOL", "req": ["quadcopter", "lithium_ion_battery", "electric_aircraft", "brushless_dc_motor"], "desc": "Battery-electric aircraft that take off vertically with many rotors, developed as air taxis; Volocopter flew first in 2011."},
{"id": "galileo_gnss", "name": "Galileo navigation system", "year": 2011, "cat": "aerospace", "wiki": "Galileo (satellite navigation system)", "req": ["gps"], "desc": "The European Union's civilian global satellite navigation system, with its first operational satellites in 2011."},
{"id": "curiosity_rover", "name": "Curiosity rover", "year": 2012, "cat": "aerospace", "wiki": "Curiosity (rover)", "req": ["mars_rover", "rtg"], "desc": "A car-sized nuclear-powered Mars rover lowered by a rocket sky crane in 2012."},
{"id": "rosetta", "name": "Rosetta", "year": 2014, "cat": "aerospace", "wiki": "Rosetta (spacecraft)", "req": ["gravity_assist", "space_probe"], "desc": "The first spacecraft to orbit a comet, which landed the Philae probe on its surface in 2014."},
{"id": "booster_landing", "name": "Reusable orbital booster", "year": 2015, "cat": "aerospace", "wiki": "Reusable launch vehicle", "req": ["falcon_9", "vtvl"], "desc": "A first stage that lands itself for reuse; a Falcon 9 booster first landed after an orbital launch in December 2015."},
{"id": "new_horizons", "name": "New Horizons", "year": 2015, "cat": "aerospace", "wiki": "New Horizons", "req": ["rtg", "gravity_assist"], "desc": "The probe that made the first flyby of Pluto in 2015."},
{"id": "new_shepard", "name": "New Shepard", "year": 2015, "cat": "aerospace", "wiki": "New Shepard", "req": ["vtvl", "liquid_rocket"], "desc": "Blue Origin's suborbital rocket, the first booster to fly to space and land vertically, in November 2015."},
{"id": "delivery_drone", "name": "Delivery drone", "year": 2016, "cat": "aerospace", "wiki": "Delivery drone", "req": ["uav", "gps", "lithium_ion_battery"], "desc": "An uncrewed aircraft that carries packages; Zipline began regular medical deliveries in Rwanda in 2016."},
{"id": "parker_solar_probe", "name": "Parker Solar Probe", "year": 2018, "cat": "aerospace", "wiki": "Parker Solar Probe", "req": ["gravity_assist", "space_probe"], "desc": "A heat-shielded probe that flies through the Sun's corona, the fastest object ever built."},
{"id": "electron_rocket", "name": "Electron rocket", "year": 2018, "cat": "aerospace", "wiki": "Rocket Lab Electron", "req": ["multistage_rocket", "lithium_ion_battery", "electron_beam_melting"], "desc": "A small launcher with 3D-printed, battery-pumped engines, dedicated to launching small satellites."},
{"id": "raptor_engine", "name": "Raptor engine", "year": 2019, "cat": "aerospace", "wiki": "SpaceX Raptor", "req": ["staged_combustion"], "desc": "The first full-flow staged combustion engine to fly, burning methane and liquid oxygen."},
{"id": "starlink", "name": "Starlink", "year": 2019, "cat": "aerospace", "wiki": "Starlink", "req": ["iridium", "booster_landing", "internet", "communications_satellite"], "desc": "A constellation of thousands of low-orbit satellites providing broadband internet worldwide."},
{"id": "crew_dragon", "name": "Crew Dragon", "year": 2020, "cat": "aerospace", "wiki": "SpaceX Dragon 2", "req": ["spacex_dragon", "booster_landing"], "desc": "The first commercially built and operated spacecraft to carry astronauts to orbit, in 2020."},
{"id": "hayabusa2", "name": "Hayabusa2", "year": 2020, "cat": "aerospace", "wiki": "Hayabusa2", "req": ["hayabusa"], "desc": "A Japanese probe that returned samples from asteroid Ryugu in 2020, including material from below its surface."},
{"id": "tiangong", "name": "Tiangong space station", "year": 2021, "cat": "aerospace", "wiki": "Tiangong space station", "req": ["mir"], "desc": "China's modular space station, assembled from 2021 and permanently crewed."},
{"id": "perseverance_rover", "name": "Perseverance rover", "year": 2021, "cat": "aerospace", "wiki": "Perseverance (rover)", "req": ["curiosity_rover"], "desc": "A Mars rover caching rock cores for future return to Earth; it landed in Jezero Crater in 2021."},
{"id": "ingenuity", "name": "Ingenuity helicopter", "year": 2021, "cat": "aerospace", "wiki": "Ingenuity (helicopter)", "req": ["helicopter", "perseverance_rover", "lithium_ion_battery"], "desc": "A small solar-charged helicopter that made the first powered flight on another planet, on Mars in 2021."},
{"id": "jwst", "name": "James Webb Space Telescope", "year": 2021, "cat": "aerospace", "wiki": "James Webb Space Telescope", "req": ["hubble", "segmented_mirror"], "desc": "A large infrared space telescope with a folding segmented mirror, observing the earliest galaxies."},
{"id": "dart", "name": "DART", "year": 2022, "cat": "aerospace", "wiki": "Double Asteroid Redirection Test", "req": ["space_probe"], "desc": "The first test of planetary defense, which changed an asteroid's orbit by deliberately crashing into it."},
{"id": "artemis_program", "name": "Artemis program", "year": 2022, "cat": "aerospace", "wiki": "Artemis program", "req": ["saturn_v", "space_shuttle"], "desc": "NASA's program to return humans to the Moon, starting with the uncrewed Artemis I flight in 2022."},
{"id": "starship", "name": "Starship", "year": 2023, "cat": "aerospace", "wiki": "SpaceX Starship", "req": ["raptor_engine", "booster_landing", "stainless_steel"], "desc": "The largest rocket ever flown, designed for full reuse; its booster was first caught by the launch tower in 2024."},
{"id": "osiris_rex", "name": "OSIRIS-REx", "year": 2023, "cat": "aerospace", "wiki": "OSIRIS-REx", "req": ["sample_return", "space_probe"], "desc": "NASA's first asteroid sample return, bringing material from asteroid Bennu to Earth in 2023."},
{"id": "chandrayaan_3", "name": "Chandrayaan-3", "year": 2023, "cat": "aerospace", "wiki": "Chandrayaan-3", "req": ["space_probe"], "desc": "India's first soft landing on the Moon, and the first near its south polar region, in 2023."},
{"id": "chang_e_6", "name": "Chang'e 6", "year": 2024, "cat": "aerospace", "wiki": "Chang'e 6", "req": ["sample_return"], "desc": "A Chinese mission that returned the first samples from the far side of the Moon in 2024."},
{"id": "emmer_wheat", "name": "Emmer wheat", "year": -9500, "cat": "agriculture", "wiki": "Emmer", "req": ["agriculture"], "desc": "One of the first domesticated cereals in the Fertile Crescent, a founder crop of Neolithic farming."},
{"id": "einkorn_wheat", "name": "Einkorn wheat", "year": -8500, "cat": "agriculture", "wiki": "Einkorn", "req": ["agriculture"], "desc": "Diploid wheat domesticated in southeastern Anatolia, among the earliest cultivated cereals."},
{"id": "common_wheat", "name": "Bread wheat", "year": -6500, "cat": "agriculture", "wiki": "Common wheat", "req": ["emmer_wheat"], "desc": "Hexaploid wheat from a natural cross of emmer and wild goatgrass, now the world's main wheat."},
{"id": "barley", "name": "Barley domestication", "year": -8500, "cat": "agriculture", "wiki": "Barley", "req": ["agriculture"], "desc": "Founder crop of the Near East used for food, fodder and brewing."},
{"id": "foxtail_millet", "name": "Foxtail millet", "year": -8000, "cat": "agriculture", "wiki": "Foxtail millet", "req": ["agriculture"], "desc": "Millet domesticated in northern China, the staple of early Yellow River farming."},
{"id": "rice_cultivation", "name": "Rice domestication", "year": -7000, "cat": "agriculture", "wiki": "History of rice cultivation", "req": ["agriculture"], "desc": "Domestication of Asian rice in the Yangtze valley, later the staple of much of humanity."},
{"id": "paddy_field", "name": "Paddy field", "year": -5000, "cat": "agriculture", "wiki": "Paddy field", "req": ["rice_cultivation", "irrigation"], "desc": "Flooded, bunded fields for wet rice that suppress weeds and sustain high yields."},
{"id": "soybean", "name": "Soybean domestication", "year": -5000, "cat": "agriculture", "wiki": "Soybean", "req": ["agriculture"], "desc": "Legume domesticated in East Asia, a major source of protein and oil."},
{"id": "maize", "name": "Maize domestication", "year": -7000, "cat": "agriculture", "wiki": "Maize", "req": ["agriculture"], "desc": "Domestication of teosinte into maize in southern Mexico, the basis of Mesoamerican farming."},
{"id": "potato", "name": "Potato domestication", "year": -6000, "cat": "agriculture", "wiki": "History of the potato", "req": ["agriculture"], "desc": "Domestication of the potato in the Andes, later a staple that fed Europe's population growth."},
{"id": "cassava", "name": "Cassava domestication", "year": -7000, "cat": "agriculture", "wiki": "Cassava", "req": ["agriculture"], "desc": "Starchy root domesticated in southwestern Amazonia, now a staple across the tropics."},
{"id": "sorghum", "name": "Sorghum domestication", "year": -3000, "cat": "agriculture", "wiki": "Sorghum", "req": ["agriculture"], "desc": "Drought-tolerant cereal domesticated in Africa."},
{"id": "olive", "name": "Olive cultivation", "year": -5000, "cat": "agriculture", "wiki": "Olive", "req": ["agriculture"], "desc": "Domesticated olive tree of the Levant, source of oil, food and lamp fuel."},
{"id": "viticulture", "name": "Viticulture", "year": -6000, "cat": "agriculture", "wiki": "Viticulture", "req": ["agriculture"], "desc": "Cultivation of the grapevine, begun in the South Caucasus, the basis of winemaking."},
{"id": "sugarcane", "name": "Sugarcane domestication", "year": -6000, "cat": "agriculture", "wiki": "Sugarcane", "req": ["agriculture"], "desc": "Giant grass domesticated in New Guinea, later the world's main source of sugar."},
{"id": "cotton", "name": "Cotton cultivation", "year": -5000, "cat": "agriculture", "wiki": "Cotton", "req": ["agriculture"], "desc": "Independent domestication of cotton in South Asia and the Americas for fibre."},
{"id": "tea", "name": "Tea cultivation", "year": -200, "cat": "agriculture", "wiki": "History of tea", "req": ["agriculture"], "desc": "Cultivation and processing of the tea plant in China, later a global crop."},
{"id": "coffee", "name": "Coffee cultivation", "year": 1450, "cat": "agriculture", "wiki": "History of coffee", "req": ["agriculture", "control_of_fire"], "desc": "Roasting and brewing coffee seeds, begun in Yemen and spread worldwide as a cash crop."},
{"id": "cacao_chocolate", "name": "Cacao and chocolate", "year": -1900, "cat": "agriculture", "wiki": "History of chocolate", "req": ["agriculture", "fermentation_food"], "desc": "Fermenting and roasting cacao beans into drink, first in Mesoamerica."},
{"id": "sheep", "name": "Sheep domestication", "year": -9000, "cat": "agriculture", "wiki": "Sheep", "req": ["domestication_of_animals"], "desc": "Domestication of mouflon into sheep in the Near East, for meat, milk and later wool."},
{"id": "goat", "name": "Goat domestication", "year": -8500, "cat": "agriculture", "wiki": "Goat", "req": ["domestication_of_animals"], "desc": "Goats domesticated in the Zagros, among the first livestock."},
{"id": "pig", "name": "Pig domestication", "year": -8500, "cat": "agriculture", "wiki": "Pig", "req": ["domestication_of_animals"], "desc": "Wild boar domesticated independently in Anatolia and China."},
{"id": "cattle", "name": "Cattle domestication", "year": -8500, "cat": "agriculture", "wiki": "Cattle", "req": ["domestication_of_animals"], "desc": "Domestication of the aurochs, providing meat, milk, hides and draught power."},
{"id": "chicken", "name": "Chicken domestication", "year": -1500, "cat": "agriculture", "wiki": "Chicken", "req": ["domestication_of_animals"], "desc": "Red junglefowl domesticated in Southeast Asia, now the most numerous livestock."},
{"id": "horse_domestication", "name": "Horse domestication", "year": -3500, "cat": "agriculture", "wiki": "Domestication of the horse", "req": ["domestication_of_animals"], "desc": "Taming of the horse on the Eurasian steppe for milk, riding and traction."},
{"id": "sericulture", "name": "Sericulture", "year": -3500, "cat": "agriculture", "wiki": "Sericulture", "req": ["domestication_of_animals", "agriculture"], "desc": "Rearing domesticated silkworms on mulberry leaves to produce silk, begun in China."},
{"id": "beekeeping", "name": "Beekeeping", "year": -2400, "cat": "agriculture", "wiki": "Beekeeping", "req": ["domestication_of_animals", "pottery"], "desc": "Keeping honey bees in hives for honey and wax, shown in Egyptian reliefs."},
{"id": "langstroth_hive", "name": "Langstroth hive", "year": 1852, "cat": "agriculture", "wiki": "Langstroth hive", "req": ["beekeeping"], "desc": "Hive with removable frames spaced by the bee space, the basis of modern beekeeping."},
{"id": "pastoralism", "name": "Pastoralism", "year": -8000, "cat": "agriculture", "wiki": "Pastoralism", "req": ["sheep", "goat"], "desc": "Herding livestock across pasture as a way of life, spreading farming into marginal lands."},
{"id": "dairy", "name": "Dairying", "year": -7000, "cat": "agriculture", "wiki": "Dairy", "req": ["cattle", "sheep", "goat", "pottery"], "desc": "Milking livestock and processing milk, shown by milk residues in Neolithic pottery."},
{"id": "yoke", "name": "Yoke", "year": -4000, "cat": "agriculture", "wiki": "Yoke", "req": ["cattle", "domestication_of_animals"], "desc": "Wooden beam joining draught oxen so they can pull a plough or cart."},
{"id": "horseshoe", "name": "Horseshoe", "year": 500, "cat": "agriculture", "wiki": "Horseshoe", "req": ["horse_domestication", "iron_working", "hipposandal"], "desc": "Nailed iron shoe protecting hooves, letting horses work on hard and wet ground."},
{"id": "horse_collar", "name": "Horse collar", "year": 500, "cat": "agriculture", "wiki": "Horse collar", "req": ["horse_domestication", "yoke"], "desc": "Padded collar resting on the shoulders that let horses pull heavy loads without choking."},
{"id": "selective_breeding", "name": "Systematic selective breeding", "year": 1760, "cat": "agriculture", "wiki": "Selective breeding", "req": ["domestication_of_animals", "agriculture"], "desc": "Deliberate breeding for chosen traits, systematized for livestock by Robert Bakewell."},
{"id": "artificial_insemination", "name": "Artificial insemination", "year": 1784, "cat": "agriculture", "wiki": "Artificial insemination", "req": ["selective_breeding", "microscope"], "desc": "Introducing semen without mating, first shown by Spallanzani and later central to cattle breeding."},
{"id": "battery_cage", "name": "Battery cage", "year": 1930, "cat": "agriculture", "wiki": "Battery cage", "req": ["chicken", "steel"], "desc": "Wire cages housing laying hens in rows, enabling industrial egg production."},
{"id": "antibiotic_livestock", "name": "Antibiotics in livestock", "year": 1950, "cat": "agriculture", "wiki": "Antibiotic use in livestock", "req": ["penicillin", "cattle"], "desc": "Routine antibiotics in feed to promote growth, which accelerated antimicrobial resistance."},
{"id": "intensive_animal_farming", "name": "Intensive animal farming", "year": 1950, "cat": "agriculture", "wiki": "Intensive animal farming", "req": ["battery_cage", "antibiotic_livestock", "broiler"], "desc": "Confining large numbers of animals indoors for industrial meat, egg and milk output."},
{"id": "barbed_wire", "name": "Barbed wire", "year": 1874, "cat": "agriculture", "wiki": "Barbed wire", "req": ["steel"], "desc": "Cheap wire fencing with sharp barbs that enclosed open rangeland."},
{"id": "electric_fence", "name": "Electric fence", "year": 1936, "cat": "agriculture", "wiki": "Electric fence", "req": ["barbed_wire", "electrical_grid"], "desc": "Fence delivering pulsed shocks to contain livestock cheaply."},
{"id": "automatic_milking", "name": "Automatic milking", "year": 1992, "cat": "agriculture", "wiki": "Automatic milking", "req": ["vacuum_pump", "dairy", "microprocessor"], "desc": "Robotic milking systems that milk cows without a human operator."},
{"id": "milk_separator", "name": "Cream separator", "year": 1878, "cat": "agriculture", "wiki": "Separator (milk)", "req": ["dairy", "gear"], "desc": "Centrifuge that separates cream from milk, industrializing butter making."},
{"id": "sickle", "name": "Sickle", "year": -10000, "cat": "agriculture", "wiki": "Sickle", "req": ["stone_tools", "hafting"], "desc": "Curved blade for reaping cereals, first made of flint set in bone or wood."},
{"id": "hoe", "name": "Hoe", "year": -8000, "cat": "agriculture", "wiki": "Hoe (tool)", "req": ["agriculture"], "desc": "Hand tool for breaking soil and weeding, the main tillage tool before the plough."},
{"id": "quern", "name": "Quern-stone", "year": -13000, "cat": "agriculture", "wiki": "Quern-stone", "req": ["stone_tools", "ground_stone"], "desc": "Hand-operated grinding stones for turning grain into flour."},
{"id": "granary", "name": "Granary", "year": -9500, "cat": "agriculture", "wiki": "Granary", "req": ["agriculture"], "desc": "Dedicated storehouse for threshed grain, allowing surplus and planning."},
{"id": "winnowing", "name": "Winnowing", "year": -8000, "cat": "agriculture", "wiki": "Winnowing", "req": ["agriculture"], "desc": "Separating grain from chaff by tossing it in the wind."},
{"id": "threshing_board", "name": "Threshing board", "year": -6000, "cat": "agriculture", "wiki": "Threshing board", "req": ["agriculture", "domestication_of_animals", "stone_tools"], "desc": "Flint-studded sledge dragged by animals over grain to thresh it."},
{"id": "scythe", "name": "Scythe", "year": -500, "cat": "agriculture", "wiki": "Scythe", "req": ["sickle", "iron_working"], "desc": "Long-bladed mowing tool for cutting hay and grain standing upright."},
{"id": "carruca", "name": "Heavy plough", "year": 600, "cat": "agriculture", "wiki": "Carruca", "req": ["plough", "iron_working", "wheel"], "desc": "Wheeled mouldboard plough that turned heavy clay soils of northern Europe."},
{"id": "seed_drill", "name": "Seed drill", "year": -200, "cat": "agriculture", "wiki": "Seed drill", "req": ["plough"], "desc": "Device that sows seeds in rows at set depth, used in Han China and improved by Jethro Tull."},
{"id": "slash_and_burn", "name": "Slash-and-burn agriculture", "year": -7000, "cat": "agriculture", "wiki": "Slash-and-burn agriculture", "req": ["agriculture", "control_of_fire"], "desc": "Clearing forest by cutting and burning for temporary fields."},
{"id": "crop_rotation", "name": "Crop rotation", "year": -6000, "cat": "agriculture", "wiki": "Crop rotation", "req": ["agriculture", "lentil"], "desc": "Alternating crops on a field to restore fertility and break pest cycles."},
{"id": "three_field_system", "name": "Three-field system", "year": 800, "cat": "agriculture", "wiki": "Three-field system", "req": ["crop_rotation", "carruca"], "desc": "Medieval rotation of winter grain, spring crop and fallow that raised output."},
{"id": "norfolk_rotation", "name": "Norfolk four-course system", "year": 1730, "cat": "agriculture", "wiki": "Norfolk four-course system", "req": ["three_field_system"], "desc": "Rotation of wheat, turnips, barley and clover that eliminated fallow."},
{"id": "terracing", "name": "Terrace farming", "year": -3000, "cat": "agriculture", "wiki": "Terrace (earthworks)", "req": ["agriculture", "irrigation", "dry_stone"], "desc": "Stepped fields cut into hillsides to farm slopes and control erosion."},
{"id": "shadoof", "name": "Shadoof", "year": -2300, "cat": "agriculture", "wiki": "Shadoof", "req": ["irrigation", "lever"], "desc": "Counterweighted lever for lifting water, used in Mesopotamia and Egypt."},
{"id": "qanat", "name": "Qanat", "year": -800, "cat": "agriculture", "wiki": "Qanat", "req": ["irrigation", "surveying"], "desc": "Gently sloping underground channel bringing groundwater to fields in arid Iran."},
{"id": "noria", "name": "Noria", "year": -300, "cat": "agriculture", "wiki": "Noria", "req": ["water_wheel", "irrigation"], "desc": "Current-driven wheel with pots that lifts river water for irrigation."},
{"id": "saqiyah", "name": "Saqiyah", "year": -300, "cat": "agriculture", "wiki": "Saqiyah", "req": ["gear", "irrigation", "domestication_of_animals"], "desc": "Animal-driven geared wheel that raises water from wells and canals."},
{"id": "chinampa", "name": "Chinampa", "year": 1150, "cat": "agriculture", "wiki": "Chinampa", "req": ["irrigation", "maize"], "desc": "Raised fields built in shallow lakes by Mesoamerican farmers, highly productive."},
{"id": "tile_drainage", "name": "Tile drainage", "year": 1835, "cat": "agriculture", "wiki": "Tile drainage", "req": ["pottery", "kiln"], "desc": "Buried clay pipes that drain waterlogged fields, opening wet soils to farming."},
{"id": "windpump", "name": "Windpump", "year": 1854, "cat": "agriculture", "wiki": "Windpump", "req": ["windmill", "tower_mill"], "desc": "Self-regulating wind-driven pump that watered livestock on dry plains."},
{"id": "center_pivot", "name": "Center-pivot irrigation", "year": 1948, "cat": "agriculture", "wiki": "Center-pivot irrigation", "req": ["irrigation", "electric_motor"], "desc": "Rotating sprinkler arm watering circular fields from a central well."},
{"id": "drip_irrigation", "name": "Drip irrigation", "year": 1959, "cat": "agriculture", "wiki": "Drip irrigation", "req": ["irrigation", "bakelite", "polyethylene"], "desc": "Delivering water slowly to plant roots through plastic tubing, saving water."},
{"id": "greenhouse", "name": "Greenhouse", "year": 1450, "cat": "agriculture", "wiki": "Greenhouse", "req": ["glass", "agriculture"], "desc": "Glazed structure that traps heat to grow plants out of season."},
{"id": "grafting", "name": "Grafting", "year": -2000, "cat": "agriculture", "wiki": "Grafting", "req": ["agriculture"], "desc": "Joining a scion to a rootstock to propagate fruit trees true to type."},
{"id": "agricultural_chemistry", "name": "Agricultural chemistry", "year": 1840, "cat": "agriculture", "wiki": "Agricultural chemistry", "req": ["modern_chemistry"], "desc": "Liebig's chemistry of plant nutrition, which showed which minerals crops need."},
{"id": "manure", "name": "Manuring", "year": -6000, "cat": "agriculture", "wiki": "Manure", "req": ["agriculture", "domestication_of_animals"], "desc": "Spreading animal dung on fields to return nutrients to the soil."},
{"id": "guano", "name": "Guano fertilizer", "year": 1840, "cat": "agriculture", "wiki": "Guano", "req": ["agricultural_chemistry", "manure"], "desc": "Seabird and bat droppings mined and shipped as a rich nitrogen and phosphate fertilizer."},
{"id": "superphosphate", "name": "Superphosphate", "year": 1842, "cat": "agriculture", "wiki": "Superphosphate", "req": ["agricultural_chemistry", "lead_chamber_process"], "desc": "Phosphate rock treated with sulfuric acid, the first manufactured fertilizer."},
{"id": "synthetic_fertilizer", "name": "Synthetic nitrogen fertilizer", "year": 1913, "cat": "agriculture", "wiki": "Fertilizer", "req": ["haber_process", "superphosphate"], "desc": "Industrially made nitrogen fertilizer from ammonia, which now feeds billions."},
{"id": "pesticide", "name": "Pesticide", "year": -2500, "cat": "agriculture", "wiki": "Pesticide", "req": ["agriculture"], "desc": "Substances that kill crop pests, from Sumerian sulfur dusts onward."},
{"id": "biological_pest_control", "name": "Biological pest control", "year": 300, "cat": "agriculture", "wiki": "Biological pest control", "req": ["agriculture"], "desc": "Using natural enemies against pests, from Chinese citrus ants to imported beetles."},
{"id": "paris_green", "name": "Paris green", "year": 1867, "cat": "agriculture", "wiki": "Paris green", "req": ["pesticide", "modern_chemistry"], "desc": "Copper arsenite insecticide used against the Colorado potato beetle."},
{"id": "bordeaux_mixture", "name": "Bordeaux mixture", "year": 1885, "cat": "agriculture", "wiki": "Bordeaux mixture", "req": ["pesticide", "modern_chemistry"], "desc": "Copper sulfate and lime fungicide that saved vineyards from downy mildew."},
{"id": "lead_arsenate", "name": "Lead arsenate", "year": 1892, "cat": "agriculture", "wiki": "Lead hydrogen arsenate", "req": ["pesticide", "modern_chemistry"], "desc": "Arsenical insecticide widely sprayed on orchards until DDT replaced it."},
{"id": "bt_biopesticide", "name": "Bt biopesticide", "year": 1938, "cat": "agriculture", "wiki": "Bacillus thuringiensis", "req": ["biological_pest_control", "germ_theory"], "desc": "Bacterium whose insecticidal toxins were sold as a spray from 1938."},
{"id": "ddt", "name": "DDT", "year": 1939, "cat": "agriculture", "wiki": "DDT", "req": ["pesticide", "modern_chemistry"], "desc": "Synthetic organochlorine insecticide whose insecticidal action was found in 1939."},
{"id": "herbicide_2_4_d", "name": "2,4-D", "year": 1945, "cat": "agriculture", "wiki": "2,4-D", "req": ["pesticide", "modern_chemistry"], "desc": "First selective synthetic herbicide, killing broadleaf weeds in cereal crops."},
{"id": "sterile_insect", "name": "Sterile insect technique", "year": 1954, "cat": "agriculture", "wiki": "Sterile insect technique", "req": ["biological_pest_control", "x_ray"], "desc": "Releasing irradiated sterile males to collapse pest populations."},
{"id": "ipm", "name": "Integrated pest management", "year": 1959, "cat": "agriculture", "wiki": "Integrated pest management", "req": ["ddt", "biological_pest_control"], "desc": "Combining monitoring, biological control and targeted spraying to limit pesticide use."},
{"id": "paraquat", "name": "Paraquat", "year": 1962, "cat": "agriculture", "wiki": "Paraquat", "req": ["herbicide_2_4_d"], "desc": "Fast-acting contact herbicide that made no-till farming practical."},
{"id": "no_till", "name": "No-till farming", "year": 1962, "cat": "agriculture", "wiki": "No-till farming", "req": ["paraquat", "seed_drill"], "desc": "Planting without ploughing, using herbicides for weeds, to cut erosion."},
{"id": "glyphosate", "name": "Glyphosate", "year": 1974, "cat": "agriculture", "wiki": "Glyphosate", "req": ["herbicide_2_4_d"], "desc": "Broad-spectrum herbicide sold as Roundup, the most used herbicide."},
{"id": "neonicotinoid", "name": "Neonicotinoid", "year": 1991, "cat": "agriculture", "wiki": "Neonicotinoid", "req": ["pesticide", "modern_chemistry"], "desc": "Systemic nicotine-like insecticides, later restricted over harm to bees."},
{"id": "plant_breeding", "name": "Scientific plant breeding", "year": 1866, "cat": "agriculture", "wiki": "Plant breeding", "req": ["agriculture", "scientific_method"], "desc": "Systematic crossing and selection of crops, put on a genetic footing by Mendel's pea work."},
{"id": "hybrid_corn", "name": "Hybrid corn", "year": 1922, "cat": "agriculture", "wiki": "Hybrid seed", "req": ["plant_breeding", "maize", "mendelian_inheritance", "selective_breeding"], "desc": "Crossing inbred lines to exploit hybrid vigour, which raised maize yields sharply."},
{"id": "mutation_breeding", "name": "Mutation breeding", "year": 1928, "cat": "agriculture", "wiki": "Mutation breeding", "req": ["plant_breeding", "x_ray"], "desc": "Inducing mutations with radiation or chemicals to create new crop varieties."},
{"id": "norin_10", "name": "Norin 10 wheat", "year": 1935, "cat": "agriculture", "wiki": "Norin 10 wheat", "req": ["plant_breeding", "common_wheat"], "desc": "Japanese semi-dwarf wheat whose dwarfing genes underlie Green Revolution wheats."},
{"id": "seed_bank", "name": "Seed bank", "year": 1926, "cat": "agriculture", "wiki": "Seed bank", "req": ["plant_breeding"], "desc": "Collections of stored seed to preserve crop genetic diversity, begun by Vavilov."},
{"id": "high_yielding_variety", "name": "High-yielding varieties", "year": 1961, "cat": "agriculture", "wiki": "High-yielding variety", "req": ["norin_10", "hybrid_corn", "synthetic_fertilizer"], "desc": "Short-strawed crop varieties that respond to fertilizer without lodging."},
{"id": "ir8", "name": "IR8 rice", "year": 1966, "cat": "agriculture", "wiki": "IR8", "req": ["high_yielding_variety", "rice_cultivation"], "desc": "Semi-dwarf 'miracle rice' from IRRI that doubled rice yields in Asia."},
{"id": "green_revolution", "name": "Green Revolution", "year": 1966, "cat": "agriculture", "wiki": "Green Revolution", "req": ["high_yielding_variety", "ir8", "synthetic_fertilizer", "ddt"], "desc": "Spread of high-yield seed, fertilizer, pesticide and irrigation that averted famines."},
{"id": "gm_crops", "name": "Genetically modified crops", "year": 1983, "cat": "agriculture", "wiki": "Genetically modified crops", "req": ["recombinant_dna", "plant_breeding"], "desc": "Crops carrying engineered genes, first created as transgenic tobacco in 1983."},
{"id": "flavr_savr", "name": "Flavr Savr tomato", "year": 1994, "cat": "agriculture", "wiki": "Flavr Savr", "req": ["gm_crops", "gm_plant"], "desc": "First commercially sold genetically engineered whole food, a slow-softening tomato."},
{"id": "bt_cotton", "name": "Bt cotton", "year": 1996, "cat": "agriculture", "wiki": "Bt cotton", "req": ["gm_crops", "bt_biopesticide", "cotton"], "desc": "Cotton producing Bacillus thuringiensis toxin to resist bollworms."},
{"id": "bt_maize", "name": "Bt maize", "year": 1996, "cat": "agriculture", "wiki": "Genetically modified maize", "req": ["gm_crops", "bt_biopesticide", "maize"], "desc": "Insect-resistant genetically modified maize, now widely grown."},
{"id": "gm_soybean", "name": "Herbicide-tolerant soybean", "year": 1996, "cat": "agriculture", "wiki": "Genetically modified soybean", "req": ["gm_crops", "glyphosate", "soybean"], "desc": "Glyphosate-tolerant Roundup Ready soybean, the most planted GM crop."},
{"id": "golden_rice", "name": "Golden rice", "year": 2000, "cat": "agriculture", "wiki": "Golden rice", "req": ["gm_crops", "rice_cultivation", "gm_plant"], "desc": "Rice engineered to make beta-carotene to fight vitamin A deficiency."},
{"id": "aquaculture", "name": "Aquaculture", "year": -4600, "cat": "agriculture", "wiki": "Aquaculture", "req": ["stone_tools"], "desc": "Farming fish and other aquatic organisms, as in the Budj Bim eel traps of Australia."},
{"id": "oyster_farming", "name": "Oyster farming", "year": -100, "cat": "agriculture", "wiki": "Oyster farming", "req": ["aquaculture"], "desc": "Cultivating oysters on beds or ropes, practised by the Romans."},
{"id": "fish_hatchery", "name": "Fish hatchery", "year": 1842, "cat": "agriculture", "wiki": "Fish hatchery", "req": ["aquaculture"], "desc": "Artificial spawning and rearing of fish to stock waters and farms."},
{"id": "salmon_farming", "name": "Salmon farming", "year": 1970, "cat": "agriculture", "wiki": "Aquaculture of salmonids", "req": ["fish_hatchery"], "desc": "Raising salmon in sea cages, begun at scale in Norway."},
{"id": "aquaponics", "name": "Aquaponics", "year": 1980, "cat": "agriculture", "wiki": "Aquaponics", "req": ["recirculating_aquaculture", "hydroponics"], "desc": "Combining fish farming with hydroponics so fish waste feeds plants."},
{"id": "aquadvantage_salmon", "name": "AquAdvantage salmon", "year": 2015, "cat": "agriculture", "wiki": "AquAdvantage salmon", "req": ["salmon_farming", "recombinant_dna"], "desc": "Fast-growing genetically engineered salmon, the first GM animal approved as food."},
{"id": "hydroponics", "name": "Hydroponics", "year": 1929, "cat": "agriculture", "wiki": "Hydroponics", "req": ["agricultural_chemistry", "greenhouse"], "desc": "Growing plants in mineral nutrient solutions without soil."},
{"id": "vertical_farming", "name": "Vertical farming", "year": 2010, "cat": "agriculture", "wiki": "Vertical farming", "req": ["hydroponics", "light_bulb", "light_emitting_diode"], "desc": "Growing crops in stacked indoor layers under artificial light."},
{"id": "precision_agriculture", "name": "Precision agriculture", "year": 1992, "cat": "agriculture", "wiki": "Precision agriculture", "req": ["satellite", "personal_computer", "tractor", "gps"], "desc": "Using satellite positioning and field data to vary inputs across a field."},
{"id": "agricultural_drone", "name": "Agricultural drone", "year": 1990, "cat": "agriculture", "wiki": "Agricultural drone", "req": ["aerial_application", "microprocessor", "uav"], "desc": "Unmanned aircraft for spraying and monitoring crops, first used for rice in Japan."},
{"id": "agricultural_robot", "name": "Agricultural robot", "year": 2010, "cat": "agriculture", "wiki": "Agricultural robot", "req": ["precision_agriculture", "artificial_intelligence"], "desc": "Robots that weed, pick or monitor crops autonomously."},
{"id": "cotton_gin", "name": "Cotton gin", "year": 1793, "cat": "agriculture", "wiki": "Cotton gin", "req": ["cotton", "gear", "crank"], "desc": "Eli Whitney's machine for separating cotton fibre from seeds."},
{"id": "threshing_machine", "name": "Threshing machine", "year": 1786, "cat": "agriculture", "wiki": "Threshing machine", "req": ["gear", "winnowing"], "desc": "Andrew Meikle's machine that beat grain from straw, replacing the flail."},
{"id": "reaper", "name": "Mechanical reaper", "year": 1831, "cat": "agriculture", "wiki": "Reaper", "req": ["scythe", "gear", "horse_domestication"], "desc": "Horse-drawn machine that cut grain, commercialized by McCormick."},
{"id": "combine_harvester", "name": "Combine harvester", "year": 1835, "cat": "agriculture", "wiki": "Combine harvester", "req": ["reaper", "threshing_machine"], "desc": "Machine that reaps, threshes and winnows grain in one pass."},
{"id": "grain_elevator", "name": "Grain elevator", "year": 1842, "cat": "agriculture", "wiki": "Grain elevator", "req": ["steam_engine", "granary"], "desc": "Steam-powered bucket elevator and storage tower for bulk grain."},
{"id": "silo", "name": "Tower silo", "year": 1873, "cat": "agriculture", "wiki": "Silo", "req": ["granary"], "desc": "Tall structure for storing grain or fermented fodder."},
{"id": "silage", "name": "Silage", "year": 1877, "cat": "agriculture", "wiki": "Silage", "req": ["silo", "fermentation_food", "cattle"], "desc": "Fermented, high-moisture fodder that keeps cattle fed through winter."},
{"id": "traction_engine", "name": "Traction engine", "year": 1859, "cat": "agriculture", "wiki": "Traction engine", "req": ["steam_engine", "wagon"], "desc": "Self-propelled steam engine for ploughing, threshing and haulage on farms."},
{"id": "tractor", "name": "Tractor", "year": 1892, "cat": "agriculture", "wiki": "Tractor", "req": ["internal_combustion_engine", "traction_engine"], "desc": "Gasoline-powered farm vehicle that replaced draught animals."},
{"id": "fordson", "name": "Fordson tractor", "year": 1917, "cat": "agriculture", "wiki": "Fordson", "req": ["tractor", "assembly_line"], "desc": "Mass-produced, affordable tractor that brought mechanization to small farms."},
{"id": "three_point_hitch", "name": "Three-point hitch", "year": 1926, "cat": "agriculture", "wiki": "Three-point hitch", "req": ["tractor"], "desc": "Harry Ferguson's linkage attaching implements rigidly to a tractor's hydraulics."},
{"id": "cotton_picker", "name": "Cotton picker", "year": 1943, "cat": "agriculture", "wiki": "Cotton picker", "req": ["tractor", "cotton"], "desc": "Machine that harvests seed cotton, ending hand-picking in the US South."},
{"id": "gristmill", "name": "Gristmill", "year": -250, "cat": "agriculture", "wiki": "Gristmill", "req": ["quern", "water_wheel"], "desc": "Water-powered mill grinding grain into flour."},
{"id": "roller_mill", "name": "Roller mill", "year": 1839, "cat": "agriculture", "wiki": "Roller mill", "req": ["gristmill", "steam_engine", "cast_iron"], "desc": "Mill that crushes grain between rollers, producing fine white flour in bulk."},
{"id": "olive_oil_extraction", "name": "Olive oil extraction", "year": -5000, "cat": "agriculture", "wiki": "Olive oil extraction", "req": ["olive", "lever", "quern"], "desc": "Crushing and pressing olives to obtain oil."},
{"id": "sugar", "name": "Sugar crystallization", "year": 350, "cat": "agriculture", "wiki": "History of sugar", "req": ["sugarcane", "control_of_fire"], "desc": "Boiling cane juice into crystalline sugar, developed in India."},
{"id": "sugar_beet", "name": "Beet sugar", "year": 1801, "cat": "agriculture", "wiki": "Sugar beet", "req": ["sugar", "modern_chemistry"], "desc": "Extracting sugar from beets, first factory in Silesia in 1801."},
{"id": "hfcs", "name": "High-fructose corn syrup", "year": 1957, "cat": "agriculture", "wiki": "High-fructose corn syrup", "req": ["glucose_syrup", "maize"], "desc": "Corn syrup converted enzymatically to fructose, a cheap industrial sweetener."},
{"id": "food_drying", "name": "Food drying", "year": -12000, "cat": "agriculture", "wiki": "Food drying", "req": ["stone_tools"], "desc": "Preserving food by removing water in sun, wind or smoke."},
{"id": "smoking_food", "name": "Smoking", "year": -9000, "cat": "agriculture", "wiki": "Smoking (cooking)", "req": ["control_of_fire", "food_drying"], "desc": "Exposing meat and fish to smoke to dry, flavour and preserve them."},
{"id": "salting", "name": "Salting", "year": -3000, "cat": "agriculture", "wiki": "Salting (food)", "req": ["food_drying"], "desc": "Preserving meat and fish with salt, which draws out water."},
{"id": "pickling", "name": "Pickling", "year": -2400, "cat": "agriculture", "wiki": "Pickling", "req": ["salting", "pottery"], "desc": "Preserving food in brine or vinegar."},
{"id": "fermentation_food", "name": "Food fermentation", "year": -7000, "cat": "agriculture", "wiki": "Fermentation in food processing", "req": ["agriculture", "pottery"], "desc": "Using microbes to transform and preserve food and drink."},
{"id": "beer", "name": "Beer brewing", "year": -7000, "cat": "agriculture", "wiki": "History of beer", "req": ["fermentation_food", "barley"], "desc": "Fermenting malted cereals into beer, among the oldest prepared drinks."},
{"id": "wine", "name": "Winemaking", "year": -6000, "cat": "agriculture", "wiki": "History of wine", "req": ["viticulture", "fermentation_food"], "desc": "Fermenting grape juice into wine in pottery jars."},
{"id": "cheese", "name": "Cheesemaking", "year": -5500, "cat": "agriculture", "wiki": "History of cheese", "req": ["dairy", "fermentation_food"], "desc": "Curdling and draining milk to make a storable food."},
{"id": "bread", "name": "Bread", "year": -12400, "cat": "agriculture", "wiki": "History of bread", "req": ["quern", "control_of_fire"], "desc": "Baking ground grain dough, first as flatbread by hunter-gatherers."},
{"id": "sourdough", "name": "Leavened bread", "year": -3000, "cat": "agriculture", "wiki": "Sourdough", "req": ["bread", "fermentation_food"], "desc": "Bread raised by wild yeast and bacteria, made in ancient Egypt."},
{"id": "noodles", "name": "Noodles", "year": -2000, "cat": "agriculture", "wiki": "Noodles", "req": ["foxtail_millet", "quern"], "desc": "Strands of dough, the oldest known found at Lajia in China."},
{"id": "nixtamalization", "name": "Nixtamalization", "year": -1500, "cat": "agriculture", "wiki": "Nixtamalization", "req": ["maize", "pottery"], "desc": "Cooking maize in alkaline solution, which unlocks niacin and makes masa."},
{"id": "ice_house", "name": "Ice house", "year": -1700, "cat": "agriculture", "wiki": "Ice house (building)", "req": ["mudbrick"], "desc": "Insulated building for storing natural ice through summer."},
{"id": "pasteurization", "name": "Pasteurization", "year": 1864, "cat": "agriculture", "wiki": "Pasteurization", "req": ["germ_theory", "wine", "microbiology", "fermentation_food"], "desc": "Mild heating to kill spoilage microbes, devised by Pasteur for wine."},
{"id": "condensed_milk", "name": "Condensed milk", "year": 1856, "cat": "agriculture", "wiki": "Condensed milk", "req": ["dairy", "canning"], "desc": "Milk concentrated with sugar and canned, keeping without refrigeration."},
{"id": "baking_powder", "name": "Baking powder", "year": 1843, "cat": "agriculture", "wiki": "Baking powder", "req": ["modern_chemistry", "bread"], "desc": "Chemical leavening that releases carbon dioxide, replacing yeast for quick breads."},
{"id": "margarine", "name": "Margarine", "year": 1869, "cat": "agriculture", "wiki": "Margarine", "req": ["modern_chemistry", "dairy"], "desc": "Butter substitute invented by Mège-Mouriès, later made from vegetable oils."},
{"id": "reefer_ship", "name": "Refrigerated ship", "year": 1877, "cat": "agriculture", "wiki": "Reefer ship", "req": ["refrigeration", "steamship"], "desc": "Ship with refrigerated holds that carried frozen meat across oceans."},
{"id": "refrigerator_car", "name": "Refrigerator car", "year": 1878, "cat": "agriculture", "wiki": "Refrigerator car", "req": ["refrigeration", "railway"], "desc": "Insulated railcar that carried chilled meat from Chicago to eastern cities."},
{"id": "cold_chain", "name": "Cold chain", "year": 1938, "cat": "agriculture", "wiki": "Cold chain", "req": ["refrigerator_car", "automobile"], "desc": "Unbroken refrigerated supply chain, completed by refrigerated trucks."},
{"id": "freeze_drying", "name": "Freeze drying", "year": 1906, "cat": "agriculture", "wiki": "Freeze drying", "req": ["vacuum_pump", "refrigeration"], "desc": "Removing water from frozen food under vacuum by sublimation."},
{"id": "uht", "name": "UHT processing", "year": 1913, "cat": "agriculture", "wiki": "Ultra-high-temperature processing", "req": ["pasteurization"], "desc": "Heating milk briefly above 135 C to sterilize it for months of storage."},
{"id": "iodised_salt", "name": "Iodised salt", "year": 1924, "cat": "agriculture", "wiki": "Iodised salt", "req": ["salting", "modern_chemistry"], "desc": "Salt fortified with iodine to prevent goitre."},
{"id": "frozen_food", "name": "Quick-frozen food", "year": 1924, "cat": "agriculture", "wiki": "Frozen food", "req": ["refrigeration"], "desc": "Clarence Birdseye's rapid freezing that preserved food texture."},
{"id": "food_irradiation", "name": "Food irradiation", "year": 1957, "cat": "agriculture", "wiki": "Food irradiation", "req": ["x_ray", "nuclear_reactor"], "desc": "Exposing food to ionizing radiation to kill pathogens and extend shelf life."},
{"id": "instant_noodles", "name": "Instant noodles", "year": 1958, "cat": "agriculture", "wiki": "Instant noodles", "req": ["noodles", "food_drying"], "desc": "Pre-cooked, flash-fried noodles invented by Momofuku Ando."},
{"id": "textured_vegetable_protein", "name": "Textured vegetable protein", "year": 1960, "cat": "agriculture", "wiki": "Textured vegetable protein", "req": ["soybean", "tofu"], "desc": "Defatted soy flour extruded into a meat-like texture."},
{"id": "chorleywood", "name": "Chorleywood bread process", "year": 1961, "cat": "agriculture", "wiki": "Chorleywood bread process", "req": ["bread", "electric_motor"], "desc": "High-speed mixing process for fast, cheap industrial bread."},
{"id": "aseptic_processing", "name": "Aseptic packaging", "year": 1961, "cat": "agriculture", "wiki": "Aseptic processing", "req": ["uht", "canning"], "desc": "Filling sterilized food into sterile cartons, enabling shelf-stable milk."},
{"id": "single_cell_protein", "name": "Single-cell protein", "year": 1968, "cat": "agriculture", "wiki": "Single-cell protein", "req": ["fermentation_food", "oil_refining", "industrial_fermentation"], "desc": "Protein from microbes grown in fermenters, tried as feed and food."},
{"id": "mycoprotein", "name": "Mycoprotein", "year": 1985, "cat": "agriculture", "wiki": "Mycoprotein", "req": ["single_cell_protein", "fungiculture"], "desc": "Fungal protein grown by fermentation and sold as Quorn."},
{"id": "chymosin", "name": "Fermentation-produced chymosin", "year": 1990, "cat": "agriculture", "wiki": "Chymosin", "req": ["cheese", "recombinant_dna"], "desc": "Rennet enzyme made by engineered microbes, the first recombinant food ingredient."},
{"id": "cultured_meat", "name": "Cultured meat", "year": 2013, "cat": "agriculture", "wiki": "Cultured meat", "req": ["cattle", "recombinant_dna", "tissue_engineering", "bioreactor"], "desc": "Meat grown from animal cells in culture, first shown as a burger in 2013."},
{"id": "plant_based_meat", "name": "Plant-based meat", "year": 2016, "cat": "agriculture", "wiki": "Meat alternative", "req": ["textured_vegetable_protein", "recombinant_dna"], "desc": "Meat analogues from plant proteins, some with fermented heme for flavour."},
{"id": "precision_fermentation", "name": "Precision fermentation", "year": 2019, "cat": "agriculture", "wiki": "Precision fermentation", "req": ["chymosin"], "desc": "Engineered microbes producing specific food proteins such as animal-free whey."},
{"id": "dutch_process_cocoa", "name": "Cocoa powder", "year": 1828, "cat": "agriculture", "wiki": "Dutch process cocoa", "req": ["cacao_chocolate", "lever"], "desc": "Van Houten's pressing and alkalizing of cacao that made cocoa powder and solid chocolate possible."},
{"id": "lentil", "name": "Lentil", "year": -8000, "cat": "agriculture", "wiki": "Lentil", "req": ["agriculture"], "desc": "Early domesticated legume of the Fertile Crescent that fixes nitrogen and supplied protein."},
{"id": "common_bean", "name": "Common bean", "year": -5000, "cat": "agriculture", "wiki": "Phaseolus vulgaris", "req": ["agriculture"], "desc": "Legume domesticated in Mesoamerica and the Andes, part of the maize-bean-squash complex."},
{"id": "banana", "name": "Banana cultivation", "year": -5000, "cat": "agriculture", "wiki": "Banana", "req": ["agriculture"], "desc": "Bananas cultivated in New Guinea and spread across the tropics as a staple."},
{"id": "squash", "name": "Squash domestication", "year": -8000, "cat": "agriculture", "wiki": "Cucurbita", "req": ["agriculture"], "desc": "Cucurbita squashes, among the first plants domesticated in the Americas."},
{"id": "llama", "name": "Llama domestication", "year": -4000, "cat": "agriculture", "wiki": "Llama", "req": ["domestication_of_animals"], "desc": "Andean camelid domesticated from the guanaco as a pack animal and fibre source."},
{"id": "water_buffalo", "name": "Water buffalo domestication", "year": -3000, "cat": "agriculture", "wiki": "Water buffalo", "req": ["domestication_of_animals"], "desc": "Buffalo domesticated in South and East Asia, the draught animal of rice farming."},
{"id": "domestic_turkey", "name": "Turkey domestication", "year": -300, "cat": "agriculture", "wiki": "Domestic turkey", "req": ["domestication_of_animals"], "desc": "Wild turkey domesticated in Mesoamerica for meat and feathers."},
{"id": "dromedary", "name": "Camel domestication", "year": -1000, "cat": "agriculture", "wiki": "Dromedary", "req": ["domestication_of_animals"], "desc": "One-humped camel domesticated in Arabia, enabling desert herding and caravans."},
{"id": "transhumance", "name": "Transhumance", "year": -5000, "cat": "agriculture", "wiki": "Transhumance", "req": ["pastoralism"], "desc": "Seasonal movement of herds between summer and winter pastures."},
{"id": "secondary_products", "name": "Secondary products revolution", "year": -4000, "cat": "agriculture", "wiki": "Secondary products revolution", "req": ["dairy", "sheep"], "desc": "Use of animals for milk, wool and traction rather than only meat."},
{"id": "livestock_branding", "name": "Livestock branding", "year": -2700, "cat": "agriculture", "wiki": "Livestock branding", "req": ["cattle", "smelting", "control_of_fire"], "desc": "Marking animals with hot irons to show ownership, recorded in ancient Egypt."},
{"id": "butter", "name": "Butter", "year": -2500, "cat": "agriculture", "wiki": "Butter", "req": ["dairy"], "desc": "Churning cream into a storable fat, shown in Sumerian reliefs."},
{"id": "egg_incubator", "name": "Egg incubator", "year": -400, "cat": "agriculture", "wiki": "Incubator (egg)", "req": ["chicken", "mudbrick"], "desc": "Heated chambers for hatching eggs, used at scale in ancient Egyptian egg ovens."},
{"id": "broiler", "name": "Broiler chicken", "year": 1948, "cat": "agriculture", "wiki": "Broiler", "req": ["chicken", "selective_breeding"], "desc": "Chicken breeds selected for very fast growth, the basis of industrial meat poultry."},
{"id": "feedlot", "name": "Feedlot", "year": 1950, "cat": "agriculture", "wiki": "Feedlot", "req": ["cattle", "hybrid_corn"], "desc": "Confined yards where cattle are fattened on grain before slaughter."},
{"id": "sheep_shearing", "name": "Mechanical sheep shearing", "year": 1888, "cat": "agriculture", "wiki": "Sheep shearing", "req": ["sheep", "gear"], "desc": "Shearing wool with powered handpieces, first commercialized by Wolseley in Australia."},
{"id": "semen_cryopreservation", "name": "Semen cryopreservation", "year": 1949, "cat": "agriculture", "wiki": "Semen cryopreservation", "req": ["artificial_insemination", "refrigeration"], "desc": "Freezing semen with glycerol, which let elite bulls sire offspring worldwide."},
{"id": "genomic_selection", "name": "Genomic selection", "year": 2008, "cat": "agriculture", "wiki": "Genomic selection", "req": ["selective_breeding", "dna_sequencing"], "desc": "Predicting breeding value from genome-wide markers, transforming dairy cattle breeding."},
{"id": "harrow", "name": "Harrow", "year": -500, "cat": "agriculture", "wiki": "Harrow (tool)", "req": ["plough"], "desc": "Implement dragged over ploughed land to break clods and cover seed."},
{"id": "terra_preta", "name": "Terra preta", "year": -450, "cat": "agriculture", "wiki": "Terra preta", "req": ["slash_and_burn", "pottery"], "desc": "Charcoal-enriched anthropogenic soils created by Amazonian farmers."},
{"id": "green_manure", "name": "Green manure", "year": -300, "cat": "agriculture", "wiki": "Green manure", "req": ["crop_rotation"], "desc": "Ploughing in legumes or other cover crops to enrich the soil."},
{"id": "polder", "name": "Polder", "year": 1000, "cat": "agriculture", "wiki": "Polder", "req": ["irrigation", "levee"], "desc": "Low land enclosed by dikes and drained for farming, developed in the Low Countries."},
{"id": "irrigation_sprinkler", "name": "Impact sprinkler", "year": 1933, "cat": "agriculture", "wiki": "Irrigation sprinkler", "req": ["irrigation", "gear"], "desc": "Rotating sprinkler head that spreads water over fields and lawns."},
{"id": "wardian_case", "name": "Wardian case", "year": 1829, "cat": "agriculture", "wiki": "Wardian case", "req": ["glass", "greenhouse"], "desc": "Sealed glass case that let living plants survive long sea voyages."},
{"id": "fungiculture", "name": "Mushroom cultivation", "year": 1650, "cat": "agriculture", "wiki": "Fungiculture", "req": ["agriculture"], "desc": "Cultivating edible fungi on prepared substrates, begun at scale near Paris."},
{"id": "potash", "name": "Potash fertilizer", "year": 1861, "cat": "agriculture", "wiki": "Potash", "req": ["agricultural_chemistry"], "desc": "Potassium salts mined from deposits such as Stassfurt for fertilizer."},
{"id": "biofertilizer", "name": "Rhizobium inoculant", "year": 1895, "cat": "agriculture", "wiki": "Biofertilizer", "req": ["agricultural_chemistry", "germ_theory"], "desc": "Nitrogen-fixing bacteria applied to legume seed, first sold as Nitragin."},
{"id": "parathion", "name": "Parathion", "year": 1944, "cat": "agriculture", "wiki": "Parathion", "req": ["pesticide", "modern_chemistry"], "desc": "Early organophosphate insecticide, highly effective and highly toxic."},
{"id": "atrazine", "name": "Atrazine", "year": 1958, "cat": "agriculture", "wiki": "Atrazine", "req": ["herbicide_2_4_d"], "desc": "Triazine herbicide widely used on maize."},
{"id": "pyrethroid", "name": "Pyrethroid", "year": 1973, "cat": "agriculture", "wiki": "Pyrethroid", "req": ["pesticide", "modern_chemistry"], "desc": "Synthetic analogues of plant pyrethrins, stable enough for field use."},
{"id": "triticale", "name": "Triticale", "year": 1888, "cat": "agriculture", "wiki": "Triticale", "req": ["plant_breeding", "common_wheat"], "desc": "First fertile human-made cereal, a wheat-rye hybrid."},
{"id": "svalbard_vault", "name": "Svalbard Global Seed Vault", "year": 2008, "cat": "agriculture", "wiki": "Svalbard Global Seed Vault", "req": ["seed_bank", "refrigeration"], "desc": "Arctic backup vault storing duplicates of the world's seed collections."},
{"id": "marker_assisted_selection", "name": "Marker-assisted selection", "year": 1990, "cat": "agriculture", "wiki": "Marker-assisted selection", "req": ["plant_breeding", "pcr", "rflp", "selective_breeding"], "desc": "Using DNA markers linked to traits to select plants and animals faster."},
{"id": "fish_pond", "name": "Fish pond culture", "year": -1000, "cat": "agriculture", "wiki": "Fish pond", "req": ["aquaculture"], "desc": "Raising fish such as carp in managed ponds, practised in ancient China."},
{"id": "cultured_pearl", "name": "Cultured pearl", "year": 1893, "cat": "agriculture", "wiki": "Cultured pearl", "req": ["oyster_farming"], "desc": "Pearls grown by implanting a nucleus in oysters, commercialized by Mikimoto."},
{"id": "seaweed_farming", "name": "Seaweed farming", "year": 1640, "cat": "agriculture", "wiki": "Seaweed farming", "req": ["aquaculture"], "desc": "Cultivating seaweeds such as nori, begun in Japan."},
{"id": "shrimp_farming", "name": "Shrimp farming", "year": 1933, "cat": "agriculture", "wiki": "Shrimp farming", "req": ["aquaculture"], "desc": "Raising shrimp in ponds, pioneered by Motosaku Fujinaga in Japan."},
{"id": "recirculating_aquaculture", "name": "Recirculating aquaculture", "year": 1980, "cat": "agriculture", "wiki": "Recirculating aquaculture system", "req": ["aquaculture", "electric_motor"], "desc": "Land-based tanks that filter and reuse water to farm fish."},
{"id": "power_take_off", "name": "Power take-off", "year": 1918, "cat": "agriculture", "wiki": "Power take-off", "req": ["tractor", "gear"], "desc": "Drive shaft that lets a tractor power attached implements."},
{"id": "baler", "name": "Baler", "year": 1872, "cat": "agriculture", "wiki": "Baler", "req": ["threshing_machine", "screw"], "desc": "Machine that compresses hay or straw into compact bales."},
{"id": "multiple_effect_evaporator", "name": "Multiple-effect evaporator", "year": 1843, "cat": "agriculture", "wiki": "Multiple-effect evaporator", "req": ["sugar", "steam_engine"], "desc": "Norbert Rillieux's evaporator that reused steam to refine sugar efficiently."},
{"id": "rum", "name": "Rum", "year": 1650, "cat": "agriculture", "wiki": "Rum", "req": ["sugar", "distillation"], "desc": "Spirit distilled from sugarcane molasses on Caribbean plantations."},
{"id": "glucose_syrup", "name": "Glucose syrup", "year": 1811, "cat": "agriculture", "wiki": "Glucose syrup", "req": ["modern_chemistry", "potato"], "desc": "Sweet syrup from acid hydrolysis of starch, found by Kirchhoff."},
{"id": "wet_milling", "name": "Corn wet-milling", "year": 1844, "cat": "agriculture", "wiki": "Wet-milling", "req": ["maize", "steam_engine"], "desc": "Steeping and separating maize into starch, germ and gluten on an industrial scale."},
{"id": "meat_extract", "name": "Meat extract", "year": 1865, "cat": "agriculture", "wiki": "Meat extract", "req": ["agricultural_chemistry"], "desc": "Liebig's concentrated beef extract, an early industrial food."},
{"id": "infant_formula", "name": "Infant formula", "year": 1865, "cat": "agriculture", "wiki": "Infant formula", "req": ["dairy", "agricultural_chemistry"], "desc": "Manufactured breast-milk substitute, first marketed by Liebig."},
{"id": "evaporated_milk", "name": "Evaporated milk", "year": 1884, "cat": "agriculture", "wiki": "Evaporated milk", "req": ["condensed_milk"], "desc": "Unsweetened concentrated milk sterilized in cans."},
{"id": "breakfast_cereal", "name": "Breakfast cereal", "year": 1863, "cat": "agriculture", "wiki": "Breakfast cereal", "req": ["common_wheat", "bread"], "desc": "Ready-to-eat processed grain foods, starting with granula."},
{"id": "corn_flakes", "name": "Corn flakes", "year": 1894, "cat": "agriculture", "wiki": "Corn flakes", "req": ["breakfast_cereal", "maize"], "desc": "Toasted flaked maize developed by the Kellogg brothers."},
{"id": "instant_coffee", "name": "Instant coffee", "year": 1890, "cat": "agriculture", "wiki": "Instant coffee", "req": ["coffee", "food_drying"], "desc": "Dried coffee extract that dissolves in water."},
{"id": "milk_chocolate", "name": "Milk chocolate", "year": 1875, "cat": "agriculture", "wiki": "Milk chocolate", "req": ["dutch_process_cocoa", "condensed_milk"], "desc": "Chocolate made with milk, devised by Daniel Peter."},
{"id": "conching", "name": "Conching", "year": 1879, "cat": "agriculture", "wiki": "Conching", "req": ["dutch_process_cocoa"], "desc": "Rodolphe Lindt's prolonged mixing that gave chocolate its smooth texture."},
{"id": "msg", "name": "Monosodium glutamate", "year": 1908, "cat": "agriculture", "wiki": "Monosodium glutamate", "req": ["modern_chemistry"], "desc": "Isolated umami flavour compound, later made industrially by fermentation."},
{"id": "powdered_milk", "name": "Powdered milk", "year": 1855, "cat": "agriculture", "wiki": "Powdered milk", "req": ["dairy", "food_drying"], "desc": "Milk evaporated to a dry powder for long storage."},
{"id": "tofu", "name": "Tofu", "year": -200, "cat": "agriculture", "wiki": "Tofu", "req": ["soybean"], "desc": "Curdled soy milk pressed into blocks, a protein staple of East Asia."},
{"id": "soy_sauce", "name": "Soy sauce", "year": -200, "cat": "agriculture", "wiki": "Soy sauce", "req": ["soybean", "fermentation_food", "salting"], "desc": "Fermented soybean and grain seasoning that originated in Han China."},
{"id": "garum", "name": "Garum", "year": -500, "cat": "agriculture", "wiki": "Garum", "req": ["salting", "fermentation_food"], "desc": "Fermented fish sauce produced at industrial scale in the Roman world."},
{"id": "tortilla", "name": "Tortilla", "year": -500, "cat": "agriculture", "wiki": "Tortilla", "req": ["nixtamalization"], "desc": "Flatbread of nixtamalized maize, the staple of Mesoamerica."},
{"id": "stockfish", "name": "Stockfish", "year": 875, "cat": "agriculture", "wiki": "Stockfish", "req": ["food_drying"], "desc": "Unsalted cod air-dried on racks in Norway, traded across Europe."},
{"id": "ice_trade", "name": "Ice trade", "year": 1806, "cat": "agriculture", "wiki": "Ice trade", "req": ["ice_house", "sail"], "desc": "Harvesting lake ice and shipping it worldwide for cooling food."},
{"id": "icebox", "name": "Icebox", "year": 1803, "cat": "agriculture", "wiki": "Icebox", "req": ["ice_house", "yakhchal"], "desc": "Insulated cabinet cooled by blocks of ice, the domestic forerunner of the refrigerator."},
{"id": "sliced_bread", "name": "Sliced bread", "year": 1928, "cat": "agriculture", "wiki": "Sliced bread", "req": ["bread", "electric_motor"], "desc": "Machine-sliced and wrapped bread, first sold in 1928."},
{"id": "pascalization", "name": "High-pressure processing", "year": 1990, "cat": "agriculture", "wiki": "Pascalization", "req": ["pasteurization"], "desc": "Preserving food with very high pressure instead of heat."},
{"id": "veggie_burger", "name": "Veggie burger", "year": 1982, "cat": "agriculture", "wiki": "Veggie burger", "req": ["textured_vegetable_protein"], "desc": "Commercial meatless burger patty made from vegetables, grains or soy."},
{"id": "vinegar_production", "name": "Vinegar making", "year": -3000, "cat": "biotech", "wiki": "Vinegar", "req": ["fermentation_food"], "desc": "Acetic acid fermentation of alcohol by bacteria, an early controlled microbial process."},
{"id": "microbiology", "name": "Microbiology", "year": 1676, "cat": "biotech", "wiki": "Microbiology", "req": ["microscope"], "desc": "Leeuwenhoek's observation of bacteria and protists opened the study of microorganisms."},
{"id": "cell_theory", "name": "Cell theory", "year": 1839, "cat": "biotech", "wiki": "Cell theory", "req": ["microscope", "scientific_method"], "desc": "Schleiden and Schwann's principle that all living things are built from cells."},
{"id": "enzyme", "name": "Enzymes", "year": 1833, "cat": "biotech", "wiki": "Enzyme", "req": ["modern_chemistry"], "desc": "Payen's isolation of diastase revealed biological catalysts that drive chemistry in cells."},
{"id": "natural_selection", "name": "Natural selection", "year": 1859, "cat": "biotech", "wiki": "Natural selection", "req": ["selective_breeding", "linnaean_taxonomy", "stratigraphy"], "desc": "Darwin and Wallace's mechanism of evolution, the organizing theory of biology."},
{"id": "mendelian_inheritance", "name": "Mendelian inheritance", "year": 1866, "cat": "biotech", "wiki": "Mendelian inheritance", "req": ["selective_breeding", "scientific_method", "statistics"], "desc": "Mendel's pea experiments showed traits pass in discrete units with predictable ratios."},
{"id": "anaerobic_digestion", "name": "Anaerobic digestion", "year": 1859, "cat": "biotech", "wiki": "Anaerobic digestion", "req": ["microbiology", "biogas"], "desc": "Microbial breakdown of organic waste into biogas, first used at scale in Bombay and Exeter."},
{"id": "autoclave", "name": "Autoclave", "year": 1879, "cat": "biotech", "wiki": "Autoclave", "req": ["germ_theory", "steam_engine"], "desc": "A pressurized steam sterilizer that made aseptic laboratory culture routine."},
{"id": "microbiological_culture", "name": "Pure microbial culture", "year": 1881, "cat": "biotech", "wiki": "Microbiological culture", "req": ["germ_theory"], "desc": "Koch's methods for growing a single microbial species in isolation."},
{"id": "agar_plate", "name": "Agar plate", "year": 1882, "cat": "biotech", "wiki": "Agar plate", "req": ["microbiological_culture"], "desc": "Solid agar growth medium, suggested by Fanny Hesse, for isolating bacterial colonies."},
{"id": "petri_dish", "name": "Petri dish", "year": 1887, "cat": "biotech", "wiki": "Petri dish", "req": ["agar_plate", "glass"], "desc": "Julius Petri's shallow lidded glass dish, the standard vessel for culturing microbes."},
{"id": "tissue_culture", "name": "Tissue culture", "year": 1885, "cat": "biotech", "wiki": "Tissue culture", "req": ["cell_theory"], "desc": "Keeping living tissue alive outside the body, first shown by Wilhelm Roux with chick embryo."},
{"id": "zymase", "name": "Cell-free fermentation", "year": 1897, "cat": "biotech", "wiki": "Zymase", "req": ["enzyme", "fermentation_food"], "desc": "Buchner showed yeast extract without living cells could ferment sugar, founding biochemistry."},
{"id": "chromatography", "name": "Chromatography", "year": 1903, "cat": "biotech", "wiki": "Chromatography", "req": ["modern_chemistry"], "desc": "Tsvet's separation of plant pigments on a column, the basis of countless separation methods."},
{"id": "chromosome_theory", "name": "Chromosome theory of inheritance", "year": 1902, "cat": "biotech", "wiki": "Boveri–Sutton chromosome theory", "req": ["mendelian_inheritance", "cell_theory"], "desc": "Sutton and Boveri identified chromosomes as the carriers of Mendel's hereditary units."},
{"id": "cell_culture", "name": "Cell culture", "year": 1907, "cat": "biotech", "wiki": "Cell culture", "req": ["tissue_culture", "microbiological_culture", "microscope", "germ_theory"], "desc": "Ross Harrison grew nerve cells in vitro, starting the growth of animal cells outside organisms."},
{"id": "model_organism", "name": "Model organism genetics", "year": 1910, "cat": "biotech", "wiki": "Model organism", "req": ["chromosome_theory"], "desc": "Morgan's fruit fly lab showed how a fast-breeding species could reveal general genetic rules."},
{"id": "gene_mapping", "name": "Genetic mapping", "year": 1913, "cat": "biotech", "wiki": "Gene mapping", "req": ["model_organism"], "desc": "Sturtevant used recombination frequencies to draw the first linear map of genes on a chromosome."},
{"id": "activated_sludge", "name": "Activated sludge", "year": 1914, "cat": "biotech", "wiki": "Activated sludge", "req": ["microbiology", "sanitary_sewer", "germ_theory"], "desc": "Aerated microbial flocs that digest sewage, the core of modern wastewater treatment."},
{"id": "bacteriophage", "name": "Bacteriophage", "year": 1915, "cat": "biotech", "wiki": "Bacteriophage", "req": ["microbiological_culture"], "desc": "Viruses that infect bacteria, discovered by Twort and d'Herelle and later central to molecular biology."},
{"id": "abe_fermentation", "name": "Acetone-butanol fermentation", "year": 1916, "cat": "biotech", "wiki": "Acetone–butanol–ethanol fermentation", "req": ["microbiological_culture", "fermentation_food"], "desc": "Weizmann's Clostridium process for wartime acetone, the first large industrial fermentation."},
{"id": "industrial_fermentation", "name": "Industrial fermentation", "year": 1919, "cat": "biotech", "wiki": "Industrial fermentation", "req": ["abe_fermentation"], "desc": "Large-scale microbial production of chemicals such as citric acid, solvents and enzymes."},
{"id": "radioactive_tracer", "name": "Radioactive tracer", "year": 1923, "cat": "biotech", "wiki": "Radioactive tracer", "req": ["modern_chemistry", "x_ray", "radioactivity", "isotope"], "desc": "Hevesy's use of radioisotopes to follow molecules through living systems."},
{"id": "ultracentrifuge", "name": "Ultracentrifuge", "year": 1924, "cat": "biotech", "wiki": "Ultracentrifuge", "req": ["electric_motor"], "desc": "Svedberg's high-speed centrifuge for measuring and separating macromolecules."},
{"id": "mutagenesis", "name": "Induced mutagenesis", "year": 1927, "cat": "biotech", "wiki": "Mutagenesis", "req": ["x_ray", "chromosome_theory"], "desc": "Muller showed X-rays cause heritable mutations, giving breeders and geneticists a new tool."},
{"id": "griffith_experiment", "name": "Bacterial transformation discovery", "year": 1928, "cat": "biotech", "wiki": "Griffith's experiment", "req": ["microbiological_culture"], "desc": "Griffith found a heritable 'transforming principle' could pass between pneumococcus strains."},
{"id": "electrophoresis", "name": "Electrophoresis", "year": 1937, "cat": "biotech", "wiki": "Electrophoresis", "req": ["ultracentrifuge", "electrolysis"], "desc": "Tiselius separated proteins by their movement in an electric field."},
{"id": "plant_tissue_culture", "name": "Plant tissue culture", "year": 1939, "cat": "biotech", "wiki": "Plant tissue culture", "req": ["cell_culture"], "desc": "Growing plant cells and tissues on sterile media, enabling micropropagation and regeneration."},
{"id": "immunofluorescence", "name": "Immunofluorescence", "year": 1941, "cat": "biotech", "wiki": "Immunofluorescence", "req": ["microscope", "fluorescence_microscope"], "desc": "Coons tagged antibodies with fluorescent dyes to locate specific molecules in cells."},
{"id": "bioreactor", "name": "Bioreactor", "year": 1943, "cat": "biotech", "wiki": "Bioreactor", "req": ["industrial_fermentation", "penicillin"], "desc": "Stirred, aerated deep-tank vessels, developed for mass penicillin production."},
{"id": "avery_experiment", "name": "DNA as genetic material", "year": 1944, "cat": "biotech", "wiki": "Avery–MacLeod–McCarty experiment", "req": ["griffith_experiment"], "desc": "Avery, MacLeod and McCarty showed the transforming principle was DNA."},
{"id": "paper_chromatography", "name": "Paper chromatography", "year": 1944, "cat": "biotech", "wiki": "Paper chromatography", "req": ["chromatography"], "desc": "Martin and Synge's partition chromatography on paper, used to separate amino acids."},
{"id": "bacterial_conjugation", "name": "Bacterial conjugation", "year": 1946, "cat": "biotech", "wiki": "Bacterial conjugation", "req": ["microbiological_culture"], "desc": "Lederberg and Tatum found bacteria exchange genes by direct contact."},
{"id": "cell_fractionation", "name": "Cell fractionation", "year": 1946, "cat": "biotech", "wiki": "Cell fractionation", "req": ["ultracentrifuge", "cell_theory"], "desc": "Differential centrifugation to separate organelles, revealing the cell's internal machinery."},
{"id": "cryopreservation", "name": "Cryopreservation", "year": 1949, "cat": "biotech", "wiki": "Cryopreservation", "req": ["refrigeration", "cell_theory"], "desc": "Freezing cells with glycerol protectant so they survive, enabling cell banks and sperm storage."},
{"id": "transposon", "name": "Transposable elements", "year": 1950, "cat": "biotech", "wiki": "Transposable element", "req": ["chromosome_theory"], "desc": "McClintock discovered mobile genes in maize that jump within the genome."},
{"id": "edman_degradation", "name": "Edman degradation", "year": 1950, "cat": "biotech", "wiki": "Edman degradation", "req": ["chromatography"], "desc": "Stepwise chemical removal of amino acids from a protein's end for sequencing."},
{"id": "chemostat", "name": "Chemostat", "year": 1950, "cat": "biotech", "wiki": "Chemostat", "req": ["microbiological_culture"], "desc": "Monod and Szilard's continuous culture vessel for holding microbes at steady growth."},
{"id": "hela", "name": "HeLa cell line", "year": 1951, "cat": "biotech", "wiki": "HeLa", "req": ["cell_culture"], "desc": "The first immortal human cell line, taken from Henrietta Lacks without consent."},
{"id": "protein_sequencing", "name": "Protein sequencing", "year": 1951, "cat": "biotech", "wiki": "Protein sequencing", "req": ["paper_chromatography", "electrophoresis"], "desc": "Sanger determined insulin's amino acid sequence, proving proteins have defined sequences."},
{"id": "lambda_phage", "name": "Lambda phage", "year": 1951, "cat": "biotech", "wiki": "Lambda phage", "req": ["bacteriophage"], "desc": "A temperate bacterial virus that became a key genetic model and cloning vector."},
{"id": "plasmid", "name": "Plasmid", "year": 1952, "cat": "biotech", "wiki": "Plasmid", "req": ["bacterial_conjugation"], "desc": "Lederberg named the small extrachromosomal DNA circles that carry genes between bacteria."},
{"id": "nuclear_transfer", "name": "Somatic cell nuclear transfer", "year": 1952, "cat": "biotech", "wiki": "Somatic cell nuclear transfer", "req": ["cell_theory", "chromosome_theory"], "desc": "Briggs and King transplanted nuclei into frog eggs, later extended by Gurdon to body cells."},
{"id": "hershey_chase", "name": "Hershey-Chase experiment", "year": 1952, "cat": "biotech", "wiki": "Hershey–Chase experiment", "req": ["bacteriophage", "avery_experiment"], "desc": "Radiolabeled phages confirmed that DNA, not protein, carries genetic information."},
{"id": "gel_electrophoresis", "name": "Gel electrophoresis", "year": 1955, "cat": "biotech", "wiki": "Gel electrophoresis", "req": ["electrophoresis"], "desc": "Smithies' starch gel separated proteins by size and charge with high resolution."},
{"id": "cell_culture_medium", "name": "Eagle's medium", "year": 1955, "cat": "biotech", "wiki": "Eagle's minimal essential medium", "req": ["cell_culture"], "desc": "A defined nutrient medium that standardized the growth of mammalian cells."},
{"id": "size_exclusion_chromatography", "name": "Size-exclusion chromatography", "year": 1955, "cat": "biotech", "wiki": "Size-exclusion chromatography", "req": ["chromatography"], "desc": "Separating biomolecules by size through porous gel beads."},
{"id": "karyotype", "name": "Karyotyping", "year": 1956, "cat": "biotech", "wiki": "Karyotype", "req": ["cell_culture", "microscope"], "desc": "Tjio and Levan counted the 46 human chromosomes, founding clinical cytogenetics."},
{"id": "dna_polymerase", "name": "DNA polymerase", "year": 1956, "cat": "biotech", "wiki": "DNA polymerase", "req": ["dna_double_helix", "enzyme"], "desc": "Kornberg isolated the enzyme that copies DNA, later a workhorse of molecular biology."},
{"id": "cho_cell", "name": "CHO cells", "year": 1956, "cat": "biotech", "wiki": "Chinese hamster ovary cell", "req": ["cell_culture"], "desc": "Chinese hamster ovary cells, later the main host for producing therapeutic proteins."},
{"id": "central_dogma", "name": "Central dogma", "year": 1958, "cat": "biotech", "wiki": "Central dogma of molecular biology", "req": ["dna_double_helix"], "desc": "Crick's framework of information flow from DNA to RNA to protein."},
{"id": "meselson_stahl", "name": "Density-gradient centrifugation", "year": 1958, "cat": "biotech", "wiki": "Meselson–Stahl experiment", "req": ["ultracentrifuge", "dna_double_helix", "isotope"], "desc": "Meselson and Stahl's isotope gradient showed DNA replicates semiconservatively."},
{"id": "radioimmunoassay", "name": "Radioimmunoassay", "year": 1960, "cat": "biotech", "wiki": "Radioimmunoassay", "req": ["radioactive_tracer"], "desc": "Yalow and Berson measured tiny hormone levels with radiolabeled antibodies."},
{"id": "stem_cell", "name": "Stem cells", "year": 1961, "cat": "biotech", "wiki": "Stem cell", "req": ["cell_culture"], "desc": "Till and McCulloch showed bone marrow contains self-renewing cells that form blood lineages."},
{"id": "genetic_code", "name": "Genetic code", "year": 1961, "cat": "biotech", "wiki": "Genetic code", "req": ["central_dogma", "cell_free_protein_synthesis"], "desc": "Nirenberg and Matthaei cracked the first codon, leading to the full triplet code by 1966."},
{"id": "cell_free_protein_synthesis", "name": "Cell-free protein synthesis", "year": 1961, "cat": "biotech", "wiki": "Cell-free protein synthesis", "req": ["cell_fractionation", "central_dogma"], "desc": "Making proteins from cell extracts without living cells, used to decode the genetic code."},
{"id": "lac_operon", "name": "Lac operon", "year": 1961, "cat": "biotech", "wiki": "Lac operon", "req": ["central_dogma", "bacterial_conjugation"], "desc": "Jacob and Monod's model of gene regulation, later used to switch on engineered genes."},
{"id": "nucleic_acid_hybridization", "name": "Nucleic acid hybridization", "year": 1961, "cat": "biotech", "wiki": "Nucleic acid hybridization", "req": ["dna_double_helix"], "desc": "Base-pairing of complementary strands, the principle behind probes, blots and arrays."},
{"id": "biosensor", "name": "Biosensor", "year": 1962, "cat": "biotech", "wiki": "Biosensor", "req": ["enzyme", "electrolysis"], "desc": "Clark's enzyme electrode for glucose, the first device coupling biology to an electrical readout."},
{"id": "peptide_synthesis", "name": "Solid-phase peptide synthesis", "year": 1963, "cat": "biotech", "wiki": "Peptide synthesis", "req": ["protein_sequencing"], "desc": "Merrifield built peptides on resin beads, automating chemical protein synthesis."},
{"id": "dna_ligase", "name": "DNA ligase", "year": 1967, "cat": "biotech", "wiki": "DNA ligase", "req": ["dna_polymerase"], "desc": "The enzyme that seals breaks in DNA, used to join fragments in cloning."},
{"id": "hplc", "name": "HPLC", "year": 1967, "cat": "biotech", "wiki": "High-performance liquid chromatography", "req": ["chromatography"], "desc": "High-pressure liquid chromatography for fast, precise separation of biomolecules."},
{"id": "affinity_chromatography", "name": "Affinity chromatography", "year": 1968, "cat": "biotech", "wiki": "Affinity chromatography", "req": ["chromatography", "enzyme"], "desc": "Purifying a protein by its specific binding to an immobilized partner."},
{"id": "flow_cytometry", "name": "Flow cytometry", "year": 1968, "cat": "biotech", "wiki": "Flow cytometry", "req": ["immunofluorescence", "laser"], "desc": "Measuring fluorescence of single cells in a stream; extended to cell sorting by Herzenberg."},
{"id": "in_situ_hybridization", "name": "In situ hybridization", "year": 1969, "cat": "biotech", "wiki": "In situ hybridization", "req": ["nucleic_acid_hybridization", "microscope"], "desc": "Locating specific DNA or RNA sequences directly in cells and tissue sections."},
{"id": "immobilized_enzyme", "name": "Immobilized enzymes", "year": 1969, "cat": "biotech", "wiki": "Immobilized enzyme", "req": ["enzyme", "industrial_fermentation"], "desc": "Enzymes fixed to solid supports for reuse in continuous industrial processes."},
{"id": "restriction_enzyme", "name": "Restriction enzymes", "year": 1970, "cat": "biotech", "wiki": "Restriction enzyme", "req": ["bacteriophage", "dna_double_helix"], "desc": "Smith isolated enzymes that cut DNA at specific sequences, the scissors of genetic engineering."},
{"id": "reverse_transcriptase", "name": "Reverse transcriptase", "year": 1970, "cat": "biotech", "wiki": "Reverse transcriptase", "req": ["central_dogma"], "desc": "Temin and Baltimore found the enzyme that copies RNA into DNA, enabling cDNA cloning."},
{"id": "bacterial_transformation", "name": "Bacterial transformation", "year": 1970, "cat": "biotech", "wiki": "Genetic transformation", "req": ["avery_experiment", "plasmid"], "desc": "Mandel and Higa's calcium chloride method made bacteria take up foreign DNA."},
{"id": "sds_page", "name": "SDS-PAGE", "year": 1970, "cat": "biotech", "wiki": "SDS-PAGE", "req": ["gel_electrophoresis"], "desc": "Laemmli's denaturing polyacrylamide gels resolve proteins by molecular weight."},
{"id": "sequence_alignment", "name": "Sequence alignment algorithms", "year": 1970, "cat": "biotech", "wiki": "Needleman–Wunsch algorithm", "req": ["electronic_computer", "protein_sequencing"], "desc": "Dynamic programming to align biological sequences, a foundation of bioinformatics."},
{"id": "elisa", "name": "ELISA", "year": 1971, "cat": "biotech", "wiki": "ELISA", "req": ["enzyme", "immunofluorescence", "radioimmunoassay"], "desc": "Enzyme-linked immunosorbent assay for detecting proteins with antibodies and a color change."},
{"id": "protein_data_bank", "name": "Protein Data Bank", "year": 1971, "cat": "biotech", "wiki": "Protein Data Bank", "req": ["x_ray_crystallography", "electronic_computer"], "desc": "The shared archive of 3D biomolecular structures, later the training data for AlphaFold."},
{"id": "viral_vector", "name": "Viral vectors", "year": 1972, "cat": "biotech", "wiki": "Viral vector", "req": ["restriction_enzyme", "dna_ligase"], "desc": "Berg spliced foreign DNA into SV40, starting the use of viruses to deliver genes."},
{"id": "gene_synthesis", "name": "Artificial gene synthesis", "year": 1972, "cat": "biotech", "wiki": "Artificial gene synthesis", "req": ["genetic_code", "dna_ligase"], "desc": "Khorana's group chemically assembled the first synthetic gene."},
{"id": "agarose_gel", "name": "Agarose gel electrophoresis", "year": 1972, "cat": "biotech", "wiki": "Agarose gel electrophoresis", "req": ["gel_electrophoresis"], "desc": "Agarose gels for separating DNA fragments by length, routine in every molecular lab."},
{"id": "cloning_vector", "name": "Cloning vector", "year": 1973, "cat": "biotech", "wiki": "Cloning vector", "req": ["plasmid", "restriction_enzyme", "bacterial_transformation"], "desc": "Plasmids such as pSC101 engineered to carry and replicate foreign DNA in bacteria."},
{"id": "transgenic_mouse", "name": "Transgenic animals", "year": 1974, "cat": "biotech", "wiki": "Genetically modified mouse", "req": ["viral_vector", "recombinant_dna"], "desc": "Jaenisch introduced foreign DNA into mouse embryos, making the first transgenic mammal."},
{"id": "hybridoma", "name": "Hybridoma technology", "year": 1975, "cat": "biotech", "wiki": "Hybridoma technology", "req": ["cell_culture", "elisa"], "desc": "Kohler and Milstein fused B cells with myeloma cells to make monoclonal antibodies."},
{"id": "southern_blot", "name": "Southern blot", "year": 1975, "cat": "biotech", "wiki": "Southern blot", "req": ["agarose_gel", "nucleic_acid_hybridization", "restriction_enzyme"], "desc": "Edwin Southern's transfer of DNA from gels to membranes for probe detection."},
{"id": "two_d_gel", "name": "2D gel electrophoresis", "year": 1975, "cat": "biotech", "wiki": "Two-dimensional gel electrophoresis", "req": ["sds_page"], "desc": "O'Farrell separated thousands of proteins by charge then size, a precursor of proteomics."},
{"id": "bioremediation", "name": "Bioremediation", "year": 1975, "cat": "biotech", "wiki": "Bioremediation", "req": ["microbiology", "plasmid"], "desc": "Using microbes to break down pollutants such as oil spills and solvents."},
{"id": "patch_clamp", "name": "Patch clamp", "year": 1976, "cat": "biotech", "wiki": "Patch clamp", "req": ["cell_culture", "amplifier"], "desc": "Neher and Sakmann recorded currents through single ion channels in cell membranes."},
{"id": "complementary_dna", "name": "cDNA cloning", "year": 1976, "cat": "biotech", "wiki": "Complementary DNA", "req": ["reverse_transcriptase", "cloning_vector"], "desc": "DNA copies of messenger RNA, letting researchers clone expressed genes without introns."},
{"id": "expression_vector", "name": "Expression vector", "year": 1977, "cat": "biotech", "wiki": "Expression vector", "req": ["cloning_vector", "lac_operon"], "desc": "Vectors that make host cells produce a cloned protein, first used for human somatostatin."},
{"id": "pbr322", "name": "pBR322", "year": 1977, "cat": "biotech", "wiki": "PBR322", "req": ["cloning_vector"], "desc": "A compact, widely shared plasmid that became the standard E. coli cloning vector."},
{"id": "northern_blot", "name": "Northern blot", "year": 1977, "cat": "biotech", "wiki": "Northern blot", "req": ["southern_blot"], "desc": "Blotting RNA onto membranes to measure gene expression."},
{"id": "maxam_gilbert", "name": "Maxam-Gilbert sequencing", "year": 1977, "cat": "biotech", "wiki": "Maxam–Gilbert sequencing", "req": ["dna_sequencing", "gel_electrophoresis"], "desc": "Chemical cleavage method of reading DNA, published alongside Sanger's."},
{"id": "site_directed_mutagenesis", "name": "Site-directed mutagenesis", "year": 1978, "cat": "biotech", "wiki": "Site-directed mutagenesis", "req": ["gene_synthesis", "cloning_vector"], "desc": "Michael Smith's method for making precise changes at chosen positions in DNA."},
{"id": "genomic_library", "name": "Genomic library", "year": 1978, "cat": "biotech", "wiki": "Genomic library", "req": ["cloning_vector", "lambda_phage"], "desc": "Collections of cloned fragments covering an organism's genome, used to find genes."},
{"id": "algae_fuel", "name": "Algae fuel", "year": 1978, "cat": "biotech", "wiki": "Algae fuel", "req": ["industrial_fermentation"], "desc": "Growing microalgae for oils and fuels, pursued in the US Aquatic Species Program."},
{"id": "western_blot", "name": "Western blot", "year": 1979, "cat": "biotech", "wiki": "Western blot", "req": ["sds_page", "elisa"], "desc": "Transferring proteins to membranes and detecting them with antibodies."},
{"id": "rflp", "name": "RFLP analysis", "year": 1980, "cat": "biotech", "wiki": "Restriction fragment length polymorphism", "req": ["southern_blot"], "desc": "Using DNA variation in restriction fragments as genetic markers for mapping."},
{"id": "fish", "name": "Fluorescence in situ hybridization", "year": 1980, "cat": "biotech", "wiki": "Fluorescence in situ hybridization", "req": ["in_situ_hybridization", "immunofluorescence", "fluorescence_microscope"], "desc": "Fluorescent probes that light up specific DNA sequences on chromosomes."},
{"id": "embryonic_stem_cell", "name": "Embryonic stem cells", "year": 1981, "cat": "biotech", "wiki": "Embryonic stem cell", "req": ["stem_cell", "cell_culture_medium"], "desc": "Evans, Kaufman and Martin derived pluripotent mouse stem cell lines, human lines following in 1998."},
{"id": "oligonucleotide_synthesis", "name": "Oligonucleotide synthesis", "year": 1981, "cat": "biotech", "wiki": "Oligonucleotide synthesis", "req": ["gene_synthesis"], "desc": "Caruthers' phosphoramidite chemistry made automated synthesis of short DNA strands routine."},
{"id": "capillary_electrophoresis", "name": "Capillary electrophoresis", "year": 1981, "cat": "biotech", "wiki": "Capillary electrophoresis", "req": ["gel_electrophoresis"], "desc": "Electrophoresis in thin capillaries, later the basis of high-throughput DNA sequencers."},
{"id": "genbank", "name": "GenBank", "year": 1982, "cat": "biotech", "wiki": "GenBank", "req": ["dna_sequencing", "electronic_computer"], "desc": "The public database of nucleotide sequences, a pillar of open genomics."},
{"id": "shotgun_sequencing", "name": "Shotgun sequencing", "year": 1982, "cat": "biotech", "wiki": "Shotgun sequencing", "req": ["dna_sequencing", "cloning_vector"], "desc": "Sequencing random fragments and assembling them by computer, used for whole genomes."},
{"id": "electroporation", "name": "Electroporation", "year": 1982, "cat": "biotech", "wiki": "Electroporation", "req": ["cell_culture"], "desc": "Electric pulses open cell membranes so DNA can enter, a general transfection method."},
{"id": "dna_nanotechnology", "name": "DNA nanotechnology", "year": 1982, "cat": "biotech", "wiki": "DNA nanotechnology", "req": ["nucleic_acid_hybridization", "oligonucleotide_synthesis", "dna_double_helix", "nanotechnology"], "desc": "Seeman's idea of building structures from programmed DNA base pairing."},
{"id": "gm_plant", "name": "Genetically modified plant", "year": 1983, "cat": "biotech", "wiki": "Genetically modified plant", "req": ["plant_tissue_culture", "recombinant_dna"], "desc": "Agrobacterium-mediated transformation produced the first transgenic tobacco plants."},
{"id": "ancient_dna", "name": "Ancient DNA", "year": 1984, "cat": "biotech", "wiki": "Ancient DNA", "req": ["cloning_vector", "dna_sequencing"], "desc": "DNA recovered from the extinct quagga opened genetic study of the past."},
{"id": "dna_profiling", "name": "DNA profiling", "year": 1984, "cat": "biotech", "wiki": "DNA profiling", "req": ["rflp"], "desc": "Jeffreys' genetic fingerprinting identified individuals from repetitive DNA."},
{"id": "pulsed_field_gel", "name": "Pulsed-field gel electrophoresis", "year": 1984, "cat": "biotech", "wiki": "Pulsed-field gel electrophoresis", "req": ["agarose_gel"], "desc": "Alternating fields separate very large DNA molecules, even whole chromosomes."},
{"id": "cryo_em", "name": "Cryo-electron microscopy", "year": 1984, "cat": "biotech", "wiki": "Cryo-electron microscopy", "req": ["microscope", "cathode_ray_tube", "transmission_electron_microscopy", "liquid_helium"], "desc": "Imaging flash-frozen molecules by electron microscopy; atomic resolution arrived around 2013."},
{"id": "phage_display", "name": "Phage display", "year": 1985, "cat": "biotech", "wiki": "Phage display", "req": ["bacteriophage", "recombinant_dna"], "desc": "George Smith displayed proteins on phage surfaces to select binders from huge libraries."},
{"id": "maldi", "name": "MALDI mass spectrometry", "year": 1985, "cat": "biotech", "wiki": "Matrix-assisted laser desorption/ionization", "req": ["laser", "mass_spectrometry"], "desc": "A gentle laser ionization that lets mass spectrometers weigh large proteins."},
{"id": "protein_nmr", "name": "Protein NMR", "year": 1985, "cat": "biotech", "wiki": "Nuclear magnetic resonance spectroscopy of proteins", "req": ["quantum_mechanics", "electronic_computer", "nmr_spectroscopy"], "desc": "Wuthrich solved protein structures in solution by nuclear magnetic resonance."},
{"id": "dna_sequencer", "name": "Automated DNA sequencer", "year": 1986, "cat": "biotech", "wiki": "DNA sequencer", "req": ["dna_sequencing", "laser"], "desc": "Fluorescent dye sequencing machines from Hood's lab and Applied Biosystems."},
{"id": "yeast_artificial_chromosome", "name": "Yeast artificial chromosome", "year": 1987, "cat": "biotech", "wiki": "Yeast artificial chromosome", "req": ["cloning_vector"], "desc": "Vectors carrying hundreds of kilobases of DNA in yeast, used for genome mapping."},
{"id": "gene_targeting", "name": "Gene targeting", "year": 1987, "cat": "biotech", "wiki": "Gene targeting", "req": ["embryonic_stem_cell", "recombinant_dna"], "desc": "Capecchi and Smithies used homologous recombination to alter chosen genes in stem cells."},
{"id": "crispr", "name": "CRISPR arrays", "year": 1987, "cat": "biotech", "wiki": "CRISPR", "req": ["dna_sequencing"], "desc": "Repeats found in bacterial DNA, later understood as an adaptive immune system against phages."},
{"id": "gene_gun", "name": "Gene gun", "year": 1987, "cat": "biotech", "wiki": "Gene gun", "req": ["recombinant_dna"], "desc": "Shooting DNA-coated metal particles into cells, used to transform crops such as maize."},
{"id": "lipofection", "name": "Lipofection", "year": 1987, "cat": "biotech", "wiki": "Transfection", "req": ["cell_culture", "recombinant_dna"], "desc": "Felgner's cationic lipids deliver DNA into cells, a precursor of lipid nanoparticles."},
{"id": "taq_polymerase", "name": "Taq polymerase", "year": 1988, "cat": "biotech", "wiki": "Taq polymerase", "req": ["pcr"], "desc": "A heat-stable polymerase from hot-spring bacteria that let PCR be automated."},
{"id": "cre_lox", "name": "Cre-Lox recombination", "year": 1988, "cat": "biotech", "wiki": "Cre-Lox recombination", "req": ["bacteriophage", "gene_targeting"], "desc": "A phage recombinase used to delete or switch genes in specific tissues or at set times."},
{"id": "electrospray_ionization", "name": "Electrospray ionization", "year": 1988, "cat": "biotech", "wiki": "Electrospray ionization", "req": ["modern_chemistry", "mass_spectrometry"], "desc": "Fenn's spray ionization brought large biomolecules into mass spectrometry."},
{"id": "tissue_engineering", "name": "Tissue engineering", "year": 1988, "cat": "biotech", "wiki": "Tissue engineering", "req": ["cell_culture"], "desc": "Growing functional tissue from cells on scaffolds, framed by Langer and Vacanti."},
{"id": "knockout_mouse", "name": "Knockout mouse", "year": 1989, "cat": "biotech", "wiki": "Knockout mouse", "req": ["gene_targeting"], "desc": "Mice with a chosen gene disabled, the main tool for testing gene function in mammals."},
{"id": "two_hybrid", "name": "Yeast two-hybrid", "year": 1989, "cat": "biotech", "wiki": "Two-hybrid screening", "req": ["expression_vector"], "desc": "Fields and Song's yeast assay detects protein-protein interactions."},
{"id": "blast", "name": "BLAST", "year": 1990, "cat": "biotech", "wiki": "BLAST (biotechnology)", "req": ["sequence_alignment", "genbank"], "desc": "Fast heuristic search for similar sequences across databases."},
{"id": "fermentation_chymosin", "name": "Recombinant chymosin", "year": 1990, "cat": "biotech", "wiki": "Rennet", "req": ["expression_vector", "industrial_fermentation"], "desc": "Microbially made rennet for cheese, the first recombinant food enzyme approved."},
{"id": "microfluidics", "name": "Microfluidics", "year": 1990, "cat": "biotech", "wiki": "Microfluidics", "req": ["photolithography"], "desc": "Manipulating tiny fluid volumes in chips, enabling lab-on-a-chip and droplet assays."},
{"id": "bacterial_artificial_chromosome", "name": "Bacterial artificial chromosome", "year": 1992, "cat": "biotech", "wiki": "Bacterial artificial chromosome", "req": ["cloning_vector"], "desc": "Stable large-insert vectors in E. coli, the backbone of genome projects."},
{"id": "bisulfite_sequencing", "name": "Bisulfite sequencing", "year": 1992, "cat": "biotech", "wiki": "Bisulfite sequencing", "req": ["pcr", "dna_sequencing"], "desc": "Chemical conversion that reveals DNA methylation patterns, a key epigenetics method."},
{"id": "tet_system", "name": "Tet-On/Tet-Off system", "year": 1992, "cat": "biotech", "wiki": "Tetracycline-controlled transcriptional activation", "req": ["expression_vector"], "desc": "Bujard and Gossen's drug-switchable control of transgene expression."},
{"id": "qpcr", "name": "Real-time PCR", "year": 1993, "cat": "biotech", "wiki": "Real-time polymerase chain reaction", "req": ["taq_polymerase"], "desc": "Measuring DNA amplification as it happens, for quantifying genes and pathogens."},
{"id": "directed_evolution", "name": "Directed evolution", "year": 1993, "cat": "biotech", "wiki": "Directed evolution", "req": ["site_directed_mutagenesis", "pcr"], "desc": "Frances Arnold's iterative mutation and selection to engineer better enzymes."},
{"id": "gfp", "name": "Green fluorescent protein", "year": 1994, "cat": "biotech", "wiki": "Green fluorescent protein", "req": ["expression_vector"], "desc": "Chalfie expressed jellyfish GFP in other organisms, making gene activity visible in living cells."},
{"id": "dna_computing", "name": "DNA computing", "year": 1994, "cat": "biotech", "wiki": "DNA computing", "req": ["oligonucleotide_synthesis", "pcr"], "desc": "Adleman solved a path problem with DNA molecules, showing biochemistry can compute."},
{"id": "casp", "name": "CASP", "year": 1994, "cat": "biotech", "wiki": "CASP", "req": ["protein_data_bank"], "desc": "A biennial blind contest for predicting protein structures from sequence."},
{"id": "dna_microarray", "name": "DNA microarray", "year": 1995, "cat": "biotech", "wiki": "DNA microarray", "req": ["nucleic_acid_hybridization", "photolithography", "oligonucleotide_synthesis"], "desc": "Chips with thousands of DNA probes to measure expression of many genes at once."},
{"id": "proteomics", "name": "Proteomics", "year": 1995, "cat": "biotech", "wiki": "Proteomics", "req": ["two_d_gel", "electrospray_ionization", "maldi"], "desc": "Large-scale identification of the proteins in a cell by mass spectrometry."},
{"id": "zinc_finger_nuclease", "name": "Zinc-finger nuclease", "year": 1996, "cat": "biotech", "wiki": "Zinc-finger nuclease", "req": ["restriction_enzyme", "recombinant_dna"], "desc": "Chandrasegaran fused zinc-finger DNA binders to a nuclease to cut chosen sites."},
{"id": "pyrosequencing", "name": "Pyrosequencing", "year": 1996, "cat": "biotech", "wiki": "Pyrosequencing", "req": ["dna_sequencing", "enzyme"], "desc": "Sequencing by detecting light released as each nucleotide is added."},
{"id": "dolly", "name": "Dolly the sheep", "year": 1996, "cat": "biotech", "wiki": "Dolly (sheep)", "req": ["nuclear_transfer", "cell_culture"], "desc": "The first mammal cloned from an adult cell, by Wilmut and Campbell at the Roslin Institute."},
{"id": "morpholino", "name": "Morpholino antisense", "year": 1997, "cat": "biotech", "wiki": "Morpholino nucleic acid", "req": ["oligonucleotide_synthesis"], "desc": "Synthetic antisense oligos that block translation, used to knock down genes in embryos."},
{"id": "rnai", "name": "RNA interference", "year": 1998, "cat": "biotech", "wiki": "RNA interference", "req": ["central_dogma", "model_organism"], "desc": "Fire and Mello found double-stranded RNA silences matching genes."},
{"id": "digital_pcr", "name": "Digital PCR", "year": 1999, "cat": "biotech", "wiki": "Digital polymerase chain reaction", "req": ["qpcr", "microfluidics"], "desc": "Splitting a sample into many partitions to count individual DNA molecules."},
{"id": "lamp", "name": "Loop-mediated isothermal amplification", "year": 2000, "cat": "biotech", "wiki": "Loop-mediated isothermal amplification", "req": ["dna_polymerase"], "desc": "DNA amplification at one temperature, used for simple field diagnostics."},
{"id": "synthetic_circuit", "name": "Synthetic gene circuits", "year": 2000, "cat": "biotech", "wiki": "Synthetic biological circuit", "req": ["expression_vector", "lac_operon"], "desc": "The toggle switch and repressilator showed genes could be wired like electronic circuits."},
{"id": "expanded_genetic_code", "name": "Expanded genetic code", "year": 2001, "cat": "biotech", "wiki": "Expanded genetic code", "req": ["genetic_code", "directed_evolution"], "desc": "Schultz engineered cells to incorporate unnatural amino acids into proteins."},
{"id": "sirna", "name": "Small interfering RNA", "year": 2001, "cat": "biotech", "wiki": "Small interfering RNA", "req": ["rnai", "oligonucleotide_synthesis"], "desc": "Tuschl showed short synthetic RNAs trigger RNAi in mammalian cells."},
{"id": "chromosome_conformation_capture", "name": "Chromosome conformation capture", "year": 2002, "cat": "biotech", "wiki": "Chromosome conformation capture", "req": ["pcr"], "desc": "Methods (3C, later Hi-C) that map how chromosomes fold in the nucleus."},
{"id": "human_genome_project", "name": "Human Genome Project", "year": 2003, "cat": "biotech", "wiki": "Human Genome Project", "req": ["shotgun_sequencing", "dna_sequencer", "bacterial_artificial_chromosome"], "desc": "The international effort that produced a reference human genome sequence."},
{"id": "biobrick", "name": "BioBricks", "year": 2003, "cat": "biotech", "wiki": "BioBrick", "req": ["synthetic_circuit"], "desc": "Standardized interchangeable DNA parts for assembling genetic systems."},
{"id": "protein_design", "name": "Computational protein design", "year": 2003, "cat": "biotech", "wiki": "Protein design", "req": ["casp", "electronic_computer"], "desc": "Baker's lab designed Top7, a protein fold not found in nature."},
{"id": "bioprinting", "name": "3D bioprinting", "year": 2003, "cat": "biotech", "wiki": "3D bioprinting", "req": ["tissue_engineering", "3d_printing"], "desc": "Printing living cells and gels layer by layer to build tissue-like structures."},
{"id": "metagenomics", "name": "Metagenomics", "year": 2004, "cat": "biotech", "wiki": "Metagenomics", "req": ["shotgun_sequencing"], "desc": "Sequencing DNA from whole environmental samples to study unculturable microbes."},
{"id": "igem", "name": "iGEM", "year": 2004, "cat": "biotech", "wiki": "International Genetically Engineered Machine", "req": ["biobrick"], "desc": "A student competition in synthetic biology that popularized standard biological parts."},
{"id": "massively_parallel_sequencing", "name": "Next-generation sequencing", "year": 2005, "cat": "biotech", "wiki": "Massively parallel sequencing", "req": ["pyrosequencing", "microfluidics"], "desc": "454 Life Sciences sequenced millions of fragments in parallel, collapsing costs."},
{"id": "optogenetics", "name": "Optogenetics", "year": 2005, "cat": "biotech", "wiki": "Optogenetics", "req": ["viral_vector", "patch_clamp"], "desc": "Deisseroth and Boyden used light-gated channels to control neurons with precision."},
{"id": "gwas", "name": "Genome-wide association study", "year": 2005, "cat": "biotech", "wiki": "Genome-wide association study", "req": ["dna_microarray", "human_genome_project"], "desc": "Scanning many genomes for variants linked to traits and diseases."},
{"id": "illumina_sequencing", "name": "Illumina sequencing", "year": 2006, "cat": "biotech", "wiki": "Illumina dye sequencing", "req": ["massively_parallel_sequencing"], "desc": "Solexa's sequencing by synthesis with reversible terminators, the dominant short-read platform."},
{"id": "ipsc", "name": "Induced pluripotent stem cells", "year": 2006, "cat": "biotech", "wiki": "Induced pluripotent stem cell", "req": ["embryonic_stem_cell", "viral_vector"], "desc": "Yamanaka reprogrammed adult cells into stem cells with four transcription factors."},
{"id": "dna_origami", "name": "DNA origami", "year": 2006, "cat": "biotech", "wiki": "DNA origami", "req": ["dna_nanotechnology"], "desc": "Rothemund folded a long DNA strand into arbitrary shapes with short staples."},
{"id": "brainbow", "name": "Brainbow", "year": 2007, "cat": "biotech", "wiki": "Brainbow", "req": ["gfp", "cre_lox"], "desc": "Random combinations of fluorescent proteins label individual neurons in distinct colors."},
{"id": "chip_seq", "name": "ChIP-seq", "year": 2007, "cat": "biotech", "wiki": "ChIP sequencing", "req": ["illumina_sequencing"], "desc": "Sequencing DNA bound by specific proteins to map regulatory sites genome-wide."},
{"id": "chemogenetics", "name": "Chemogenetics", "year": 2007, "cat": "biotech", "wiki": "Chemogenetics", "req": ["viral_vector", "directed_evolution"], "desc": "Engineered receptors (DREADDs) that let designer drugs switch neurons on or off."},
{"id": "rna_seq", "name": "RNA-Seq", "year": 2008, "cat": "biotech", "wiki": "RNA-Seq", "req": ["illumina_sequencing", "complementary_dna"], "desc": "Sequencing cDNA to measure the whole transcriptome."},
{"id": "golden_gate", "name": "Golden Gate cloning", "year": 2008, "cat": "biotech", "wiki": "Golden Gate Cloning", "req": ["restriction_enzyme", "dna_ligase"], "desc": "One-pot assembly of many DNA parts using type IIS restriction enzymes."},
{"id": "gibson_assembly", "name": "Gibson assembly", "year": 2009, "cat": "biotech", "wiki": "Gibson assembly", "req": ["dna_ligase", "oligonucleotide_synthesis"], "desc": "Isothermal joining of overlapping DNA fragments, used to build synthetic genomes."},
{"id": "exome_sequencing", "name": "Exome sequencing", "year": 2009, "cat": "biotech", "wiki": "Exome sequencing", "req": ["illumina_sequencing"], "desc": "Sequencing just the protein-coding regions to find disease mutations cheaply."},
{"id": "single_cell_sequencing", "name": "Single-cell sequencing", "year": 2009, "cat": "biotech", "wiki": "Single-cell sequencing", "req": ["rna_seq", "microfluidics"], "desc": "Profiling the genome or transcriptome of individual cells."},
{"id": "organoid", "name": "Organoids", "year": 2009, "cat": "biotech", "wiki": "Organoid", "req": ["embryonic_stem_cell", "tissue_engineering"], "desc": "Clevers' lab grew self-organizing mini-intestines from single stem cells."},
{"id": "synthetic_genome", "name": "Synthetic genome", "year": 2010, "cat": "biotech", "wiki": "Mycoplasma laboratorium", "req": ["gibson_assembly", "nuclear_transfer"], "desc": "The J. Craig Venter Institute booted a bacterium on a chemically synthesized genome."},
{"id": "talen", "name": "TALEN", "year": 2010, "cat": "biotech", "wiki": "Transcription activator-like effector nuclease", "req": ["zinc_finger_nuclease"], "desc": "Programmable nucleases built from plant-pathogen TALE DNA-binding repeats."},
{"id": "smrt_sequencing", "name": "SMRT sequencing", "year": 2010, "cat": "biotech", "wiki": "Single-molecule real-time sequencing", "req": ["massively_parallel_sequencing"], "desc": "Pacific Biosciences' single-molecule long-read sequencing in zero-mode waveguides."},
{"id": "organ_on_a_chip", "name": "Organ-on-a-chip", "year": 2010, "cat": "biotech", "wiki": "Organ-on-a-chip", "req": ["microfluidics", "cell_culture"], "desc": "Ingber's lung-on-a-chip modeled organ function in microfluidic devices."},
{"id": "crispr_cas9", "name": "CRISPR-Cas9 gene editing", "year": 2012, "cat": "biotech", "wiki": "CRISPR gene editing", "req": ["crispr", "talen"], "desc": "Doudna and Charpentier reprogrammed Cas9 with guide RNA to cut chosen DNA sites."},
{"id": "dna_data_storage", "name": "DNA data storage", "year": 2012, "cat": "biotech", "wiki": "DNA digital data storage", "req": ["oligonucleotide_synthesis", "illumina_sequencing"], "desc": "Church encoded a book in synthetic DNA, a dense and durable storage medium."},
{"id": "clarity", "name": "CLARITY", "year": 2013, "cat": "biotech", "wiki": "CLARITY", "req": ["optogenetics"], "desc": "Making brain tissue transparent so whole organs can be imaged intact."},
{"id": "nanopore_sequencing", "name": "Nanopore sequencing", "year": 2014, "cat": "biotech", "wiki": "Nanopore sequencing", "req": ["massively_parallel_sequencing", "semiconductor"], "desc": "Reading DNA as it threads through a protein pore, in handheld long-read devices."},
{"id": "unnatural_base_pair", "name": "Unnatural base pair", "year": 2014, "cat": "biotech", "wiki": "Base pair", "req": ["expanded_genetic_code"], "desc": "Romesberg's bacteria replicated DNA with a third synthetic base pair."},
{"id": "cellulosic_ethanol", "name": "Cellulosic ethanol", "year": 2014, "cat": "biotech", "wiki": "Cellulosic ethanol", "req": ["industrial_fermentation", "enzyme", "ethanol_fuel"], "desc": "Breaking down plant fiber with enzymes into fermentable sugars for fuel."},
{"id": "gene_drive", "name": "Gene drive", "year": 2015, "cat": "biotech", "wiki": "Gene drive", "req": ["crispr_cas9"], "desc": "CRISPR constructs that copy themselves to spread through wild populations."},
{"id": "expansion_microscopy", "name": "Expansion microscopy", "year": 2015, "cat": "biotech", "wiki": "Expansion microscopy", "req": ["clarity"], "desc": "Physically swelling samples in hydrogel to see nanoscale detail with ordinary microscopes."},
{"id": "epigenome_editing", "name": "Epigenome editing", "year": 2015, "cat": "biotech", "wiki": "Epigenome editing", "req": ["crispr_cas9"], "desc": "Using catalytically dead Cas9 fused to modifiers to change gene activity without cutting DNA."},
{"id": "base_editing", "name": "Base editing", "year": 2016, "cat": "biotech", "wiki": "Genome editing", "req": ["crispr_cas9"], "desc": "David Liu's editors change single DNA letters without double-strand breaks."},
{"id": "spatial_transcriptomics", "name": "Spatial transcriptomics", "year": 2016, "cat": "biotech", "wiki": "Spatial transcriptomics", "req": ["rna_seq", "microscope"], "desc": "Measuring gene expression while keeping its position in tissue."},
{"id": "prime_editing", "name": "Prime editing", "year": 2019, "cat": "biotech", "wiki": "Prime editing", "req": ["base_editing", "reverse_transcriptase"], "desc": "A search-and-replace editor writing new sequence from an RNA template via reverse transcriptase."},
{"id": "xenobot", "name": "Xenobots", "year": 2020, "cat": "biotech", "wiki": "Xenobot", "req": ["artificial_intelligence", "cell_culture"], "desc": "Computer-designed living machines assembled from frog cells."},
{"id": "alphafold", "name": "AlphaFold", "year": 2020, "cat": "biotech", "wiki": "AlphaFold", "req": ["artificial_intelligence", "casp", "protein_data_bank"], "desc": "DeepMind's deep learning system predicted protein structures near experimental accuracy."},
{"id": "cave_painting", "name": "Cave painting", "year": -40000, "cat": "communication", "wiki": "Cave painting", "req": ["stone_tools", "control_of_fire", "ochre_pigment"], "desc": "Images painted on cave walls with ochre and charcoal, among the oldest surviving forms of symbolic visual communication."},
{"id": "petroglyph", "name": "Petroglyph", "year": -30000, "cat": "communication", "wiki": "Petroglyph", "req": ["stone_tools"], "desc": "Images pecked or carved into rock surfaces, used across the world to record and convey meaning."},
{"id": "proto_writing", "name": "Proto-writing", "year": -7000, "cat": "communication", "wiki": "Proto-writing", "req": ["agriculture"], "desc": "Systems of conventional symbols, such as marks on tokens and pottery, that carried information before full writing."},
{"id": "cylinder_seal", "name": "Cylinder seal", "year": -3500, "cat": "communication", "wiki": "Cylinder seal", "req": ["pottery", "stone_tools"], "desc": "Carved stone cylinders rolled onto clay to impress images, an early form of repeatable printing and authentication."},
{"id": "clay_tablet", "name": "Clay tablet", "year": -3200, "cat": "communication", "wiki": "Clay tablet", "req": ["writing", "pottery"], "desc": "Tablets of wet clay inscribed and then dried or fired, the main writing medium of Mesopotamia."},
{"id": "stylus", "name": "Stylus", "year": -3200, "cat": "communication", "wiki": "Stylus", "req": ["writing"], "desc": "A pointed or wedge-tipped tool for marking clay or wax, the first dedicated writing instrument."},
{"id": "cuneiform", "name": "Cuneiform", "year": -3200, "cat": "communication", "wiki": "Cuneiform", "req": ["clay_tablet", "stylus"], "desc": "Wedge-shaped Mesopotamian script pressed into clay, used for three millennia across many languages."},
{"id": "egyptian_hieroglyphs", "name": "Egyptian hieroglyphs", "year": -3200, "cat": "communication", "wiki": "Egyptian hieroglyphs", "req": ["writing"], "desc": "Formal Egyptian writing system combining logographic and phonetic signs, carved on monuments and written on papyrus."},
{"id": "ink", "name": "Ink", "year": -3200, "cat": "communication", "wiki": "Ink", "req": ["writing", "control_of_fire"], "desc": "Pigment or dye suspended in liquid, first made from soot and gum, that let writing be done quickly on soft surfaces."},
{"id": "reed_pen", "name": "Reed pen", "year": -3000, "cat": "communication", "wiki": "Reed pen", "req": ["ink", "papyrus"], "desc": "A cut reed used to write ink on papyrus, the standard pen of the ancient Mediterranean world."},
{"id": "scroll", "name": "Scroll", "year": -2500, "cat": "communication", "wiki": "Scroll", "req": ["papyrus"], "desc": "Long rolls of papyrus or leather that served as the main book format in antiquity."},
{"id": "mail", "name": "Mail", "year": -2400, "cat": "communication", "wiki": "Mail", "req": ["writing"], "desc": "Organized delivery of written messages by courier, later developed into state relay and public postal systems."},
{"id": "bamboo_slips", "name": "Bamboo and wooden slips", "year": -1200, "cat": "communication", "wiki": "Bamboo and wooden slips", "req": ["writing"], "desc": "Strips of bamboo or wood bound with cord, the main writing medium in China before paper."},
{"id": "wax_tablet", "name": "Wax tablet", "year": -800, "cat": "communication", "wiki": "Wax tablet", "req": ["writing", "stylus"], "desc": "A wooden board coated in wax for reusable notes, widely used in Greece and Rome."},
{"id": "smoke_signal", "name": "Smoke signal", "year": -800, "cat": "communication", "wiki": "Smoke signal", "req": ["control_of_fire"], "desc": "Visual signals made with smoke or beacon fires to pass warnings over long distances."},
{"id": "parchment", "name": "Parchment", "year": -200, "cat": "communication", "wiki": "Parchment", "req": ["domestication_of_animals", "writing"], "desc": "Prepared animal skin used as a durable writing surface, popularized at Pergamon."},
{"id": "codex", "name": "Codex", "year": 100, "cat": "communication", "wiki": "Codex", "req": ["parchment", "wax_tablet"], "desc": "Book made of stacked sheets bound along one edge, which replaced the scroll and allowed random access to text."},
{"id": "iron_gall_ink", "name": "Iron gall ink", "year": 400, "cat": "communication", "wiki": "Iron gall ink", "req": ["ink", "iron_working"], "desc": "Permanent ink made from iron salts and tannins, the standard European writing ink for over a thousand years."},
{"id": "quill", "name": "Quill", "year": 600, "cat": "communication", "wiki": "Quill", "req": ["parchment", "ink"], "desc": "A pen cut from a bird feather, the main Western writing tool from late antiquity to the 19th century."},
{"id": "woodblock_printing", "name": "Woodblock printing", "year": 600, "cat": "communication", "wiki": "Woodblock printing", "req": ["paper", "ink", "cylinder_seal"], "desc": "Printing from carved wooden blocks, developed in China and used for the first printed books."},
{"id": "intaglio", "name": "Intaglio printmaking", "year": 1430, "cat": "communication", "wiki": "Intaglio (printmaking)", "req": ["paper", "ink", "steel"], "desc": "Printing from images incised into a metal plate, used for engravings, maps and banknotes."},
{"id": "pencil", "name": "Pencil", "year": 1565, "cat": "communication", "wiki": "Pencil", "req": ["writing"], "desc": "Writing tool with a graphite core, later encased in wood, that made erasable marks."},
{"id": "newspaper", "name": "Newspaper", "year": 1605, "cat": "communication", "wiki": "Newspaper", "req": ["printing_press"], "desc": "Regularly printed publication of news, first issued in Strasbourg, that created a mass reading public."},
{"id": "magic_lantern", "name": "Magic lantern", "year": 1659, "cat": "communication", "wiki": "Magic lantern", "req": ["lens", "camera_obscura"], "desc": "An early image projector that threw painted glass slides onto a screen, ancestor of the film projector."},
{"id": "optical_telegraph", "name": "Optical telegraph", "year": 1792, "cat": "communication", "wiki": "Optical telegraph", "req": ["telescope", "mechanical_clock"], "desc": "Chappe's network of semaphore towers that relayed coded messages across France in minutes."},
{"id": "lithography", "name": "Lithography", "year": 1796, "cat": "communication", "wiki": "Lithography", "req": ["printing_press", "ink"], "desc": "Printing from a flat stone or plate using the repulsion of oil and water, invented by Alois Senefelder."},
{"id": "paper_machine", "name": "Paper machine", "year": 1799, "cat": "communication", "wiki": "Paper machine", "req": ["paper", "water_wheel"], "desc": "Machine that forms paper as a continuous web, the Fourdrinier type made paper cheap and plentiful."},
{"id": "dip_pen", "name": "Dip pen", "year": 1822, "cat": "communication", "wiki": "Dip pen", "req": ["quill", "steel"], "desc": "Pen with a mass-produced steel nib dipped in ink, which replaced the quill in the 19th century."},
{"id": "braille", "name": "Braille", "year": 1824, "cat": "communication", "wiki": "Braille", "req": ["alphabet", "paper"], "desc": "Tactile writing system of raised dots devised by Louis Braille for blind readers."},
{"id": "fountain_pen", "name": "Fountain pen", "year": 1827, "cat": "communication", "wiki": "Fountain pen", "req": ["dip_pen"], "desc": "Pen with an internal ink reservoir fed to the nib by capillary action."},
{"id": "phenakistiscope", "name": "Phenakistiscope", "year": 1833, "cat": "communication", "wiki": "Phenakistoscope", "req": ["paper"], "desc": "Spinning disc of sequential drawings that produced the illusion of motion, the first widespread animation device."},
{"id": "morse_code", "name": "Morse code", "year": 1838, "cat": "communication", "wiki": "Morse code", "req": ["telegraph"], "desc": "Code of dots and dashes for letters and numbers that became the global standard for telegraphy."},
{"id": "daguerreotype", "name": "Daguerreotype", "year": 1839, "cat": "communication", "wiki": "Daguerreotype", "req": ["photography"], "desc": "First commercially practical photographic process, producing detailed unique images on silvered copper."},
{"id": "postage_stamp", "name": "Postage stamp", "year": 1840, "cat": "communication", "wiki": "Postage stamp", "req": ["mail", "printing_press"], "desc": "Prepaid adhesive stamp, introduced with Britain's Penny Black, that enabled cheap uniform postal rates."},
{"id": "calotype", "name": "Calotype", "year": 1841, "cat": "communication", "wiki": "Calotype", "req": ["photography", "paper"], "desc": "Talbot's paper negative process, the first to allow multiple prints from one exposure."},
{"id": "fax", "name": "Fax", "year": 1843, "cat": "communication", "wiki": "Fax", "req": ["telegraph", "mechanical_clock"], "desc": "Transmission of scanned images over wires, first patented by Alexander Bain."},
{"id": "rotary_printing_press", "name": "Rotary printing press", "year": 1843, "cat": "communication", "wiki": "Rotary printing press", "req": ["printing_press", "steam_engine"], "desc": "Press with type or plates on a rotating cylinder, enabling very fast newspaper printing."},
{"id": "printing_telegraph", "name": "Printing telegraph", "year": 1846, "cat": "communication", "wiki": "Printing telegraph", "req": ["telegraph", "morse_code"], "desc": "Telegraph that printed received messages as text, removing the need for trained operators to read code."},
{"id": "submarine_cable", "name": "Submarine communications cable", "year": 1850, "cat": "communication", "wiki": "Submarine communications cable", "req": ["telegraph", "vulcanization", "gutta_percha"], "desc": "Insulated cable laid on the seabed to carry telegraph signals between landmasses."},
{"id": "collodion_process", "name": "Collodion process", "year": 1851, "cat": "communication", "wiki": "Collodion process", "req": ["photography", "modern_chemistry"], "desc": "Wet-plate glass negative process that cut exposure times and dominated photography for 30 years."},
{"id": "phonautograph", "name": "Phonautograph", "year": 1857, "cat": "communication", "wiki": "Phonautograph", "req": ["paper", "scientific_method"], "desc": "Scott's device that traced sound waves onto paper, the first recording of sound, though it could not play back."},
{"id": "transatlantic_telegraph_cable", "name": "Transatlantic telegraph cable", "year": 1858, "cat": "communication", "wiki": "Transatlantic telegraph cable", "req": ["submarine_cable", "morse_code", "gutta_percha", "galvanometer"], "desc": "Undersea cable linking Europe and North America, reliably operating from 1866."},
{"id": "color_photography", "name": "Color photography", "year": 1861, "cat": "communication", "wiki": "Color photography", "req": ["photography"], "desc": "Reproduction of colors in photographs, first demonstrated by Maxwell's three-color projection."},
{"id": "pantelegraph", "name": "Pantelegraph", "year": 1865, "cat": "communication", "wiki": "Pantelegraph", "req": ["fax"], "desc": "Caselli's image telegraph, the first commercial fax service, operating between Paris and Lyon."},
{"id": "stock_ticker", "name": "Ticker tape", "year": 1867, "cat": "communication", "wiki": "Ticker tape", "req": ["printing_telegraph"], "desc": "Telegraph printer that output stock prices on paper strip, giving markets near-real-time quotes."},
{"id": "typewriter", "name": "Typewriter", "year": 1868, "cat": "communication", "wiki": "Typewriter", "req": ["machine_tools", "movable_type"], "desc": "Machine that printed characters by striking inked ribbon, transforming office work and writing."},
{"id": "dry_plate", "name": "Dry plate", "year": 1871, "cat": "communication", "wiki": "Gelatin silver print", "req": ["collodion_process"], "desc": "Gelatin silver halide plate that could be stored before use, enabling factory-made photographic materials."},
{"id": "qwerty", "name": "QWERTY", "year": 1873, "cat": "communication", "wiki": "QWERTY", "req": ["typewriter"], "desc": "Keyboard layout devised for the Sholes and Glidden typewriter that remains the standard today."},
{"id": "baudot_code", "name": "Baudot code", "year": 1874, "cat": "communication", "wiki": "Baudot code", "req": ["telegraph"], "desc": "Five-bit character code for telegraphy, a forerunner of digital character encoding."},
{"id": "offset_printing", "name": "Offset printing", "year": 1875, "cat": "communication", "wiki": "Offset printing", "req": ["lithography", "vulcanization"], "desc": "Lithographic printing via a rubber blanket cylinder, which became the dominant commercial printing method."},
{"id": "microphone", "name": "Microphone", "year": 1876, "cat": "communication", "wiki": "Microphone", "req": ["telephone"], "desc": "Transducer converting sound into an electrical signal, first developed for telephony."},
{"id": "phonograph", "name": "Phonograph", "year": 1877, "cat": "communication", "wiki": "Phonograph", "req": ["phonautograph", "telephone"], "desc": "Edison's machine that recorded and replayed sound from grooves on a cylinder."},
{"id": "carbon_microphone", "name": "Carbon microphone", "year": 1878, "cat": "communication", "wiki": "Carbon microphone", "req": ["microphone"], "desc": "Microphone using carbon granules whose resistance varies with pressure, standard in telephones for a century."},
{"id": "telephone_exchange", "name": "Telephone exchange", "year": 1878, "cat": "communication", "wiki": "Telephone exchange", "req": ["telephone"], "desc": "Central switchboard where operators connected calls between subscribers."},
{"id": "chronophotography", "name": "Chronophotography", "year": 1878, "cat": "communication", "wiki": "Chronophotography", "req": ["photography"], "desc": "Sequential photographs capturing phases of motion, pioneered by Muybridge and Marey."},
{"id": "halftone", "name": "Halftone", "year": 1882, "cat": "communication", "wiki": "Halftone", "req": ["photography", "printing_press"], "desc": "Process rendering photographs as dots of varying size so they could be printed alongside text."},
{"id": "nipkow_disk", "name": "Nipkow disk", "year": 1884, "cat": "communication", "wiki": "Nipkow disk", "req": ["fax", "electric_motor", "photoconductivity"], "desc": "Spinning disc with spiral holes that scanned images line by line, the basis of mechanical television."},
{"id": "linotype", "name": "Linotype machine", "year": 1884, "cat": "communication", "wiki": "Linotype machine", "req": ["rotary_printing_press", "typewriter", "metal_casting"], "desc": "Keyboard machine that cast whole lines of type in hot metal, speeding newspaper composition."},
{"id": "roll_film", "name": "Roll film", "year": 1885, "cat": "communication", "wiki": "Roll film", "req": ["dry_plate"], "desc": "Flexible film wound on a spool, allowing many exposures without changing plates."},
{"id": "antenna", "name": "Antenna", "year": 1886, "cat": "communication", "wiki": "Antenna (radio)", "req": ["maxwell_equations"], "desc": "Conductor that radiates or captures radio waves, first used by Hertz to demonstrate electromagnetic waves."},
{"id": "gramophone_record", "name": "Gramophone record", "year": 1887, "cat": "communication", "wiki": "Phonograph record", "req": ["phonograph"], "desc": "Berliner's flat disc record, which could be mass-pressed and became the dominant recording medium."},
{"id": "box_camera", "name": "Kodak camera", "year": 1888, "cat": "communication", "wiki": "Box camera", "req": ["roll_film"], "desc": "Eastman's 1888 Kodak, a simple box camera sold loaded with roll film, which brought photography to amateurs."},
{"id": "photographic_film", "name": "Celluloid film", "year": 1889, "cat": "communication", "wiki": "Photographic film", "req": ["roll_film"], "desc": "Transparent flexible celluloid base coated with emulsion, which made motion pictures possible."},
{"id": "strowger_switch", "name": "Strowger switch", "year": 1891, "cat": "communication", "wiki": "Strowger switch", "req": ["telephone_exchange", "electromagnet"], "desc": "First automatic telephone exchange switch, letting callers connect without an operator."},
{"id": "kinetoscope", "name": "Kinetoscope", "year": 1891, "cat": "communication", "wiki": "Kinetoscope", "req": ["photographic_film", "electric_motor"], "desc": "Edison and Dickson's peephole viewer for moving pictures on film."},
{"id": "movie_film_35mm", "name": "35 mm movie film", "year": 1892, "cat": "communication", "wiki": "35 mm movie film", "req": ["photographic_film"], "desc": "Perforated 35 mm film gauge introduced by Dickson that became the worldwide cinema standard."},
{"id": "cinematograph", "name": "Cinématographe", "year": 1895, "cat": "communication", "wiki": "Cinematograph", "req": ["kinetoscope", "magic_lantern"], "desc": "Lumière brothers' camera and projector, used for the first public paying film screenings."},
{"id": "wire_recording", "name": "Wire recording", "year": 1898, "cat": "communication", "wiki": "Wire recording", "req": ["electromagnet", "telephone"], "desc": "Poulsen's magnetic recording of sound on steel wire, the first magnetic recording."},
{"id": "loading_coil", "name": "Loading coil", "year": 1899, "cat": "communication", "wiki": "Loading coil", "req": ["telephone", "electromagnet"], "desc": "Inductors placed along telephone lines to reduce distortion, extending long-distance calls."},
{"id": "rotary_dial", "name": "Rotary dial", "year": 1904, "cat": "communication", "wiki": "Rotary dial", "req": ["strowger_switch"], "desc": "Finger-wheel dial sending pulses to automatic exchanges, letting subscribers dial their own calls."},
{"id": "crystal_detector", "name": "Crystal detector", "year": 1904, "cat": "communication", "wiki": "Crystal detector", "req": ["radio"], "desc": "Semiconductor crystal contact that rectified radio signals, the first semiconductor device."},
{"id": "amplitude_modulation", "name": "Amplitude modulation", "year": 1906, "cat": "communication", "wiki": "Amplitude modulation", "req": ["radio", "alternator"], "desc": "Varying a carrier wave's strength with a signal, which first allowed voice and music to be sent by radio."},
{"id": "autochrome", "name": "Autochrome Lumière", "year": 1907, "cat": "communication", "wiki": "Autochrome Lumière", "req": ["color_photography", "dry_plate"], "desc": "First commercially successful color photography process, using dyed potato starch grains."},
{"id": "color_motion_picture_film", "name": "Color motion picture film", "year": 1908, "cat": "communication", "wiki": "Color motion picture film", "req": ["movie_film_35mm", "color_photography"], "desc": "Film recording color moving images, first commercially with Kinemacolor."},
{"id": "teleprinter", "name": "Teleprinter", "year": 1908, "cat": "communication", "wiki": "Teleprinter", "req": ["printing_telegraph", "typewriter", "baudot_code"], "desc": "Electromechanical typewriter sending and receiving text over wires, used for news wires and business."},
{"id": "headphones", "name": "Headphones", "year": 1910, "cat": "communication", "wiki": "Headphones", "req": ["telephone"], "desc": "Small loudspeakers worn over the ears, first used by radio and telephone operators."},
{"id": "regenerative_circuit", "name": "Regenerative circuit", "year": 1912, "cat": "communication", "wiki": "Regenerative circuit", "req": ["vacuum_tube", "radio", "triode"], "desc": "Armstrong's positive-feedback amplifier that made radio receivers far more sensitive."},
{"id": "superheterodyne", "name": "Superheterodyne receiver", "year": 1918, "cat": "communication", "wiki": "Superheterodyne receiver", "req": ["vacuum_tube", "radio", "heterodyne", "electronic_oscillator", "amplifier"], "desc": "Receiver that converts signals to a fixed intermediate frequency, the design used by nearly all radios since."},
{"id": "frequency_division_multiplexing", "name": "Frequency-division multiplexing", "year": 1918, "cat": "communication", "wiki": "Frequency-division multiplexing", "req": ["telephone", "vacuum_tube"], "desc": "Carrying many calls on one line on separate carrier frequencies, the basis of long-distance carrier systems."},
{"id": "crossbar_switch", "name": "Crossbar switch", "year": 1919, "cat": "communication", "wiki": "Crossbar switch", "req": ["strowger_switch"], "desc": "Matrix switch used in automatic exchanges, faster and more reliable than step-by-step switches."},
{"id": "radio_broadcasting", "name": "Radio broadcasting", "year": 1920, "cat": "communication", "wiki": "Radio broadcasting", "req": ["amplitude_modulation", "vacuum_tube"], "desc": "Scheduled transmission of programs to a mass audience, beginning with stations like KDKA."},
{"id": "wirephoto", "name": "Wirephoto", "year": 1921, "cat": "communication", "wiki": "Wirephoto", "req": ["fax", "photography", "telephone"], "desc": "Transmission of news photographs over telephone lines, letting papers print same-day pictures."},
{"id": "sound_on_film", "name": "Sound-on-film", "year": 1923, "cat": "communication", "wiki": "Sound-on-film", "req": ["vacuum_tube", "cinematograph", "microphone", "phototube"], "desc": "Recording of a soundtrack as an optical track alongside the film images."},
{"id": "shortwave_radio", "name": "Shortwave radio", "year": 1923, "cat": "communication", "wiki": "Shortwave radio", "req": ["radio", "vacuum_tube"], "desc": "Radio using high frequencies that reflect off the ionosphere, enabling intercontinental broadcasting."},
{"id": "loudspeaker", "name": "Moving-coil loudspeaker", "year": 1925, "cat": "communication", "wiki": "Loudspeaker", "req": ["electromagnet", "vacuum_tube"], "desc": "Rice and Kellogg's moving-coil speaker, the design still used to reproduce sound in most loudspeakers."},
{"id": "mechanical_television", "name": "Mechanical television", "year": 1925, "cat": "communication", "wiki": "Mechanical television", "req": ["nipkow_disk", "vacuum_tube"], "desc": "Television using spinning discs to scan images, first demonstrated by Baird."},
{"id": "sound_film", "name": "Sound film", "year": 1927, "cat": "communication", "wiki": "Sound film", "req": ["sound_on_film", "loudspeaker"], "desc": "Motion pictures with synchronized recorded sound, which transformed cinema after The Jazz Singer."},
{"id": "videotelephony", "name": "Videotelephony", "year": 1927, "cat": "communication", "wiki": "Videotelephony", "req": ["television", "telephone"], "desc": "Two-way transmission of video and audio between users, first demonstrated by AT&T in 1927."},
{"id": "magnetic_tape", "name": "Magnetic tape", "year": 1928, "cat": "communication", "wiki": "Magnetic tape", "req": ["wire_recording", "modern_chemistry"], "desc": "Plastic or paper tape coated with magnetic particles, the basis of audio, video and data recording."},
{"id": "terrestrial_television", "name": "Terrestrial television", "year": 1928, "cat": "communication", "wiki": "Terrestrial television", "req": ["television", "radio_broadcasting"], "desc": "Over-the-air television broadcasting from ground transmitters to home receivers."},
{"id": "coaxial_cable", "name": "Coaxial cable", "year": 1929, "cat": "communication", "wiki": "Coaxial cable", "req": ["telephone", "radio"], "desc": "Shielded cable with a central conductor that carries high-frequency signals with low loss."},
{"id": "microwave_transmission", "name": "Microwave relay", "year": 1931, "cat": "communication", "wiki": "Microwave transmission", "req": ["radio", "vacuum_tube"], "desc": "Point-to-point radio links at microwave frequencies, later used for nationwide telephone and TV networks."},
{"id": "stereophonic_sound", "name": "Stereophonic sound", "year": 1931, "cat": "communication", "wiki": "Stereophonic sound", "req": ["microphone", "loudspeaker", "gramophone_record"], "desc": "Blumlein's two-channel sound reproduction that creates a spatial impression of sources."},
{"id": "technicolor", "name": "Technicolor", "year": 1932, "cat": "communication", "wiki": "Technicolor", "req": ["color_motion_picture_film"], "desc": "Three-strip color film process that defined color cinema from the 1930s to the 1950s."},
{"id": "frequency_modulation", "name": "Frequency modulation", "year": 1933, "cat": "communication", "wiki": "Frequency modulation", "req": ["vacuum_tube", "radio"], "desc": "Armstrong's method of varying carrier frequency, giving radio far lower static than AM."},
{"id": "iconoscope", "name": "Iconoscope", "year": 1933, "cat": "communication", "wiki": "Iconoscope", "req": ["television", "cathode_ray_tube", "photoelectric_effect"], "desc": "Electronic camera tube by Zworykin that made practical television cameras possible."},
{"id": "reel_to_reel", "name": "Reel-to-reel tape recording", "year": 1935, "cat": "communication", "wiki": "Reel-to-reel audio tape recording", "req": ["magnetic_tape", "vacuum_tube"], "desc": "Open-reel magnetic tape recorders such as the Magnetophon, used for broadcast and studio work."},
{"id": "kodachrome", "name": "Kodachrome", "year": 1935, "cat": "communication", "wiki": "Kodachrome", "req": ["color_photography", "photographic_film"], "desc": "Subtractive color reversal film that made color photography widely accessible."},
{"id": "pulse_code_modulation", "name": "Pulse-code modulation", "year": 1937, "cat": "communication", "wiki": "Pulse-code modulation", "req": ["telephone", "vacuum_tube"], "desc": "Reeves's method of sampling and coding analog signals as numbers, the foundation of digital audio and telephony."},
{"id": "fm_broadcasting", "name": "FM broadcasting", "year": 1937, "cat": "communication", "wiki": "FM broadcasting", "req": ["frequency_modulation", "radio_broadcasting"], "desc": "Radio broadcasting with frequency modulation, offering higher fidelity and less noise."},
{"id": "xerography", "name": "Xerography", "year": 1938, "cat": "communication", "wiki": "Xerography", "req": ["photography", "electromagnetism", "photoconductivity"], "desc": "Carlson's dry copying process using electrostatic charge on a photoconductor and toner powder."},
{"id": "ballpoint_pen", "name": "Ballpoint pen", "year": 1938, "cat": "communication", "wiki": "Ballpoint pen", "req": ["fountain_pen", "steel"], "desc": "Bíró's pen dispensing quick-drying ink via a rolling ball, now the most common writing tool."},
{"id": "walkie_talkie", "name": "Walkie-talkie", "year": 1940, "cat": "communication", "wiki": "Walkie-talkie", "req": ["radio", "vacuum_tube"], "desc": "Handheld two-way radio transceiver, developed for military field use."},
{"id": "frequency_hopping", "name": "Frequency-hopping spread spectrum", "year": 1942, "cat": "communication", "wiki": "Frequency-hopping spread spectrum", "req": ["radio"], "desc": "Rapidly switching carrier frequency to resist jamming, later used in Bluetooth and cellular systems."},
{"id": "mobile_telephone_service", "name": "Mobile Telephone Service", "year": 1946, "cat": "communication", "wiki": "Mobile Telephone Service", "req": ["radio", "telephone"], "desc": "Early vehicle radiotelephone service connected to the public telephone network."},
{"id": "lp_record", "name": "LP record", "year": 1948, "cat": "communication", "wiki": "LP record", "req": ["gramophone_record", "microphone", "vacuum_tube", "pvc"], "desc": "Long-playing microgroove record at 33 1/3 rpm, holding a whole album per side."},
{"id": "instant_camera", "name": "Instant camera", "year": 1948, "cat": "communication", "wiki": "Instant camera", "req": ["photographic_film"], "desc": "Land's Polaroid camera that developed prints inside the camera within minutes."},
{"id": "cable_television", "name": "Cable television", "year": 1948, "cat": "communication", "wiki": "Cable television", "req": ["television", "coaxial_cable"], "desc": "Delivery of television over coaxial cable, first to reach areas with poor reception."},
{"id": "answering_machine", "name": "Answering machine", "year": 1949, "cat": "communication", "wiki": "Answering machine", "req": ["telephone", "wire_recording"], "desc": "Device that records callers' messages when a telephone goes unanswered."},
{"id": "pager", "name": "Pager", "year": 1949, "cat": "communication", "wiki": "Pager", "req": ["radio", "vacuum_tube"], "desc": "Small radio receiver that alerts the user to a message, widely used by doctors and businesses."},
{"id": "phototypesetting", "name": "Phototypesetting", "year": 1949, "cat": "communication", "wiki": "Phototypesetting", "req": ["photography", "linotype"], "desc": "Setting type by projecting characters onto photographic paper, replacing hot metal."},
{"id": "inkjet_printing", "name": "Inkjet printing", "year": 1951, "cat": "communication", "wiki": "Inkjet printing", "req": ["ink", "electromagnet"], "desc": "Printing by propelling tiny ink droplets onto paper, first used in chart recorders."},
{"id": "color_television", "name": "Color television", "year": 1953, "cat": "communication", "wiki": "Color television", "req": ["television", "color_photography"], "desc": "Broadcast television in color, made practical by the backward-compatible NTSC standard."},
{"id": "cinemascope", "name": "CinemaScope", "year": 1953, "cat": "communication", "wiki": "CinemaScope", "req": ["movie_film_35mm", "lens"], "desc": "Anamorphic widescreen film format that popularized wide aspect ratios in cinema."},
{"id": "transistor_radio", "name": "Transistor radio", "year": 1954, "cat": "communication", "wiki": "Transistor radio", "req": ["transistor", "radio_broadcasting"], "desc": "Small portable radio receiver using transistors, the first mass-market transistor product."},
{"id": "videotape", "name": "Videotape", "year": 1956, "cat": "communication", "wiki": "Videotape", "req": ["magnetic_tape", "television"], "desc": "Magnetic tape recording of television signals, first with Ampex's Quadruplex recorder."},
{"id": "tat1", "name": "TAT-1", "year": 1956, "cat": "communication", "wiki": "TAT-1", "req": ["submarine_cable", "coaxial_cable", "vacuum_tube"], "desc": "First transatlantic telephone cable, with submerged vacuum tube repeaters."},
{"id": "optical_fiber", "name": "Optical fiber", "year": 1956, "cat": "communication", "wiki": "Optical fiber", "req": ["glass"], "desc": "Thin glass fiber that guides light by total internal reflection, the medium of modern long-haul communication."},
{"id": "modem", "name": "Modem", "year": 1958, "cat": "communication", "wiki": "Modem", "req": ["telephone", "transistor"], "desc": "Device converting digital data to audio tones for transmission over telephone lines."},
{"id": "photocopier", "name": "Photocopier", "year": 1959, "cat": "communication", "wiki": "Photocopier", "req": ["xerography"], "desc": "Automatic office copier, launched as the Xerox 914, that made copying instant and ubiquitous."},
{"id": "telstar", "name": "Telstar", "year": 1962, "cat": "communication", "wiki": "Telstar", "req": ["communications_satellite", "microwave_transmission", "traveling_wave_tube", "solar_cell"], "desc": "First active satellite to relay live transatlantic television and telephone signals."},
{"id": "satellite_television", "name": "Satellite television", "year": 1962, "cat": "communication", "wiki": "Satellite television", "req": ["telstar", "television"], "desc": "Television delivered via communications satellites, later direct to home dishes."},
{"id": "t_carrier", "name": "T-carrier", "year": 1962, "cat": "communication", "wiki": "T-carrier", "req": ["pulse_code_modulation", "transistor"], "desc": "First digital telephone transmission system, multiplexing 24 PCM voice channels on copper pairs."},
{"id": "syncom", "name": "Syncom", "year": 1963, "cat": "communication", "wiki": "Syncom", "req": ["communications_satellite", "liquid_rocket"], "desc": "First geosynchronous communications satellites, enabling fixed ground antennas."},
{"id": "compact_cassette", "name": "Compact Cassette", "year": 1963, "cat": "communication", "wiki": "Cassette tape", "req": ["magnetic_tape", "transistor"], "desc": "Philips's small tape cassette that made recording and portable music widespread."},
{"id": "dtmf", "name": "Touch-tone dialing", "year": 1963, "cat": "communication", "wiki": "DTMF signaling", "req": ["telephone_exchange", "transistor"], "desc": "Signaling digits with pairs of audio tones, replacing pulse dialing on push-button phones."},
{"id": "electronic_switching", "name": "Electronic switching system", "year": 1965, "cat": "communication", "wiki": "Number One Electronic Switching System", "req": ["telephone_exchange", "transistor"], "desc": "First large stored-program telephone switch, controlled by a computer program."},
{"id": "ofdm", "name": "OFDM", "year": 1966, "cat": "communication", "wiki": "Orthogonal frequency-division multiplexing", "req": ["frequency_division_multiplexing", "transistor"], "desc": "Spreading data over many closely spaced orthogonal subcarriers, the basis of Wi-Fi, LTE and digital broadcasting."},
{"id": "digital_recording", "name": "Digital recording", "year": 1967, "cat": "communication", "wiki": "Digital recording", "req": ["pulse_code_modulation", "magnetic_tape"], "desc": "Storing audio as sampled numeric values, first demonstrated by NHK."},
{"id": "ccd", "name": "Charge-coupled device", "year": 1969, "cat": "communication", "wiki": "Charge-coupled device", "req": ["integrated_circuit", "photography", "mosfet", "photodiode"], "desc": "Semiconductor image sensor that converts light into electronic charge, enabling digital imaging."},
{"id": "laser_printer", "name": "Laser printer", "year": 1969, "cat": "communication", "wiki": "Laser printing", "req": ["xerography", "laser", "electronic_computer"], "desc": "Printer using a laser to draw an image on a xerographic drum, developed at Xerox PARC."},
{"id": "imax", "name": "IMAX", "year": 1970, "cat": "communication", "wiki": "IMAX", "req": ["movie_film_35mm", "cinemascope"], "desc": "Very large film format and projection system for immersive cinema."},
{"id": "vcr", "name": "Videocassette recorder", "year": 1971, "cat": "communication", "wiki": "Videocassette recorder", "req": ["videotape", "compact_cassette"], "desc": "Recorder using enclosed tape cassettes, bringing video recording to homes."},
{"id": "email", "name": "Email", "year": 1971, "cat": "communication", "wiki": "Email", "req": ["packet_switching", "electronic_computer", "time_sharing"], "desc": "Electronic messages sent between users on networked computers, first between ARPANET hosts."},
{"id": "voip", "name": "Voice over IP", "year": 1974, "cat": "communication", "wiki": "Voice over IP", "req": ["packet_switching", "pulse_code_modulation"], "desc": "Carrying voice calls as digital packets over data networks, first tested on ARPANET."},
{"id": "teletext", "name": "Teletext", "year": 1974, "cat": "communication", "wiki": "Teletext", "req": ["terrestrial_television"], "desc": "Text pages of news and information broadcast in the television signal's blanking interval."},
{"id": "digital_camera", "name": "Digital camera", "year": 1975, "cat": "communication", "wiki": "Digital camera", "req": ["ccd", "magnetic_tape"], "desc": "Camera that records images as digital data, first built at Kodak in 1975."},
{"id": "vhs", "name": "VHS", "year": 1976, "cat": "communication", "wiki": "VHS", "req": ["vcr"], "desc": "JVC's home videocassette format that dominated home video for two decades."},
{"id": "fiber_optic_communication", "name": "Fiber-optic communication", "year": 1977, "cat": "communication", "wiki": "Fiber-optic communication", "req": ["optical_fiber", "laser", "laser_diode"], "desc": "Sending information as pulses of light through optical fiber, first carrying live telephone traffic in 1977."},
{"id": "laserdisc", "name": "LaserDisc", "year": 1978, "cat": "communication", "wiki": "LaserDisc", "req": ["laser", "videotape"], "desc": "First commercial optical disc, storing analog video read by a laser."},
{"id": "cellular_network", "name": "Cellular network", "year": 1978, "cat": "communication", "wiki": "Cellular network", "req": ["mobile_phone"], "desc": "Radio network divided into cells that reuse frequencies, allowing mass mobile telephony."},
{"id": "first_generation_cellular", "name": "1G", "year": 1979, "cat": "communication", "wiki": "1G", "req": ["cellular_network"], "desc": "First-generation analog cellular networks such as NTT's in Tokyo and later AMPS."},
{"id": "walkman", "name": "Walkman", "year": 1979, "cat": "communication", "wiki": "Walkman", "req": ["compact_cassette", "headphones"], "desc": "Sony's portable cassette player that made personal mobile listening common."},
{"id": "compact_disc", "name": "Compact disc", "year": 1982, "cat": "communication", "wiki": "Compact disc", "req": ["digital_recording", "laserdisc", "laser_diode", "error_correction_code"], "desc": "Optical disc storing digital audio, which replaced vinyl and cassette as the main music format."},
{"id": "emoticon", "name": "Emoticon", "year": 1982, "cat": "communication", "wiki": "Emoticon", "req": ["email"], "desc": "Typographic faces such as :-) used to convey tone in text, proposed by Scott Fahlman."},
{"id": "camcorder", "name": "Camcorder", "year": 1983, "cat": "communication", "wiki": "Camcorder", "req": ["vcr", "ccd"], "desc": "Video camera and recorder combined in one portable unit."},
{"id": "desktop_publishing", "name": "Desktop publishing", "year": 1985, "cat": "communication", "wiki": "Desktop publishing", "req": ["personal_computer", "laser_printer", "wysiwyg", "postscript", "macintosh"], "desc": "Page layout on personal computers with laser printing, which democratized publishing."},
{"id": "tat8", "name": "TAT-8", "year": 1988, "cat": "communication", "wiki": "TAT-8", "req": ["fiber_optic_communication", "submarine_cable"], "desc": "First transatlantic fiber-optic cable, greatly increasing intercontinental capacity."},
{"id": "dsl", "name": "Digital subscriber line", "year": 1988, "cat": "communication", "wiki": "Digital subscriber line", "req": ["modem", "telephone_exchange"], "desc": "Broadband data transmission over ordinary telephone wires at frequencies above voice."},
{"id": "hdtv", "name": "High-definition television", "year": 1989, "cat": "communication", "wiki": "High-definition television", "req": ["color_television"], "desc": "Television with substantially more scan lines than standard definition, first broadcast in Japan."},
{"id": "second_generation_cellular", "name": "2G", "year": 1991, "cat": "communication", "wiki": "2G", "req": ["first_generation_cellular", "pulse_code_modulation"], "desc": "Digital cellular networks led by GSM, adding encryption and text messaging."},
{"id": "webcam", "name": "Webcam", "year": 1991, "cat": "communication", "wiki": "Webcam", "req": ["ccd", "internet"], "desc": "Video camera feeding images to a computer network, first used at Cambridge to watch a coffee pot."},
{"id": "sms", "name": "SMS", "year": 1992, "cat": "communication", "wiki": "SMS", "req": ["second_generation_cellular"], "desc": "Short text messages sent between mobile phones, which became a dominant form of communication."},
{"id": "jpeg", "name": "JPEG", "year": 1992, "cat": "communication", "wiki": "JPEG", "req": ["digital_camera", "personal_computer", "discrete_cosine_transform", "huffman_coding"], "desc": "Lossy image compression standard that made digital photographs practical to store and share."},
{"id": "mpeg1", "name": "MPEG-1", "year": 1993, "cat": "communication", "wiki": "MPEG-1", "req": ["digital_recording", "personal_computer", "discrete_cosine_transform", "huffman_coding"], "desc": "Standard for compressed digital video and audio, which included the MP3 audio format."},
{"id": "mp3", "name": "MP3", "year": 1993, "cat": "communication", "wiki": "MP3", "req": ["mpeg1", "discrete_cosine_transform"], "desc": "Perceptual audio coding format that shrank music files about tenfold, enabling digital music distribution."},
{"id": "streaming_media", "name": "Streaming media", "year": 1993, "cat": "communication", "wiki": "Streaming media", "req": ["internet", "mpeg1"], "desc": "Delivery of audio and video over a network for playback as it arrives."},
{"id": "active_pixel_sensor", "name": "CMOS image sensor", "year": 1993, "cat": "communication", "wiki": "Active-pixel sensor", "req": ["ccd", "integrated_circuit", "cmos", "photodiode"], "desc": "Image sensor with amplifiers in each pixel, cheaper and lower power than CCDs, used in phone cameras."},
{"id": "cdma", "name": "IS-95 CDMA", "year": 1995, "cat": "communication", "wiki": "CdmaOne", "req": ["second_generation_cellular", "frequency_hopping"], "desc": "First cellular standard based on code-division multiple access, sharing spectrum via spread spectrum codes."},
{"id": "mpeg2", "name": "MPEG-2", "year": 1995, "cat": "communication", "wiki": "MPEG-2", "req": ["mpeg1"], "desc": "Video compression standard used for DVD and digital television broadcasting."},
{"id": "dvd", "name": "DVD", "year": 1996, "cat": "communication", "wiki": "DVD", "req": ["compact_disc", "mpeg2"], "desc": "High-capacity optical disc for digital video, which replaced VHS for home movies."},
{"id": "mimo", "name": "MIMO", "year": 1996, "cat": "communication", "wiki": "MIMO", "req": ["antenna", "ofdm"], "desc": "Using multiple antennas to transmit parallel data streams, multiplying wireless capacity."},
{"id": "wifi", "name": "Wi-Fi", "year": 1997, "cat": "communication", "wiki": "Wi-Fi", "req": ["radio", "internet", "ethernet"], "desc": "Wireless local area networking based on IEEE 802.11, now the main way devices connect to the internet."},
{"id": "digital_television", "name": "Digital television", "year": 1998, "cat": "communication", "wiki": "Digital television", "req": ["mpeg2", "hdtv"], "desc": "Broadcast of television as compressed digital signals, replacing analog transmission."},
{"id": "portable_media_player", "name": "Portable media player", "year": 1998, "cat": "communication", "wiki": "Portable media player", "req": ["mp3", "lithium_ion_battery"], "desc": "Pocket device for storing and playing digital music files."},
{"id": "emoji", "name": "Emoji", "year": 1999, "cat": "communication", "wiki": "Emoji", "req": ["mobile_phone", "emoticon"], "desc": "Pictographs embedded in text, first designed for Japanese mobile phones and later standardized in Unicode."},
{"id": "bluetooth", "name": "Bluetooth", "year": 1999, "cat": "communication", "wiki": "Bluetooth", "req": ["frequency_hopping", "integrated_circuit", "radio", "microcontroller"], "desc": "Short-range wireless standard for linking phones, headsets and peripherals."},
{"id": "digital_cinema", "name": "Digital cinema", "year": 1999, "cat": "communication", "wiki": "Digital cinema", "req": ["digital_camera", "hdtv"], "desc": "Production and projection of films digitally instead of on photographic film."},
{"id": "camera_phone", "name": "Camera phone", "year": 2000, "cat": "communication", "wiki": "Camera phone", "req": ["mobile_phone", "active_pixel_sensor"], "desc": "Mobile phone with a built-in camera, which made photography constant and instantly shareable."},
{"id": "gprs", "name": "GPRS", "year": 2000, "cat": "communication", "wiki": "GPRS", "req": ["second_generation_cellular", "internet"], "desc": "Packet data service on GSM networks that brought always-on internet access to phones."},
{"id": "third_generation_cellular", "name": "3G", "year": 2001, "cat": "communication", "wiki": "3G", "req": ["cdma", "gprs"], "desc": "Third-generation cellular networks providing mobile broadband for web and video."},
{"id": "h264", "name": "H.264", "year": 2003, "cat": "communication", "wiki": "Advanced Video Coding", "req": ["mpeg2"], "desc": "Efficient video compression standard used for Blu-ray, streaming and video calls."},
{"id": "podcast", "name": "Podcast", "year": 2004, "cat": "communication", "wiki": "Podcast", "req": ["mp3", "internet"], "desc": "Episodic digital audio programs distributed over the internet for download or streaming."},
{"id": "blu_ray", "name": "Blu-ray", "year": 2006, "cat": "communication", "wiki": "Blu-ray", "req": ["dvd", "h264", "gallium_nitride"], "desc": "High-density optical disc read by a blue-violet laser, storing high-definition video."},
{"id": "fourth_generation_cellular", "name": "4G", "year": 2009, "cat": "communication", "wiki": "4G", "req": ["third_generation_cellular", "ofdm", "mimo"], "desc": "All-IP cellular networks based on LTE, offering broadband speeds for smartphones."},
{"id": "fifth_generation_cellular", "name": "5G", "year": 2019, "cat": "communication", "wiki": "5G", "req": ["fourth_generation_cellular", "mimo"], "desc": "Fifth-generation cellular networks with higher speeds, lower latency and millimetre-wave bands."},
{"id": "tally_stick", "name": "Tally stick", "year": -40000, "cat": "computing", "wiki": "Tally stick", "req": ["stone_tools"], "desc": "Notched bones and sticks used to record counts, the earliest known aids to calculation."},
{"id": "abacus", "name": "Abacus", "year": -2500, "cat": "computing", "wiki": "Abacus", "req": ["numerals"], "desc": "A frame or board of movable counters for fast arithmetic, used from Sumer to modern Asia."},
{"id": "quipu", "name": "Quipu", "year": -2500, "cat": "computing", "wiki": "Quipu", "req": ["cordage", "numerals"], "desc": "Knotted cords used in the Andes to record numbers and accounts."},
{"id": "counting_rods", "name": "Counting rods", "year": -400, "cat": "computing", "wiki": "Counting rods", "req": ["numerals"], "desc": "Small rods laid out on a board for place-value arithmetic in ancient China."},
{"id": "euclidean_algorithm", "name": "Euclidean algorithm", "year": -300, "cat": "computing", "wiki": "Euclidean algorithm", "req": ["geometry"], "desc": "A step-by-step procedure for the greatest common divisor, among the oldest algorithms still in use."},
{"id": "antikythera_mechanism", "name": "Antikythera mechanism", "year": -150, "cat": "computing", "wiki": "Antikythera mechanism", "req": ["gear", "geometry", "calendar"], "desc": "A Greek geared device that computed astronomical positions and eclipses, the oldest known analog computer."},
{"id": "scytale", "name": "Scytale", "year": -400, "cat": "computing", "wiki": "Scytale", "req": ["writing"], "desc": "A rod around which a strip was wound to encipher messages by transposition."},
{"id": "caesar_cipher", "name": "Caesar cipher", "year": -58, "cat": "computing", "wiki": "Caesar cipher", "req": ["alphabet"], "desc": "A substitution cipher shifting each letter a fixed number of places."},
{"id": "frequency_analysis", "name": "Frequency analysis", "year": 850, "cat": "computing", "wiki": "Frequency analysis", "req": ["caesar_cipher"], "desc": "Al-Kindi's method of breaking substitution ciphers by counting letter frequencies."},
{"id": "vigenere_cipher", "name": "Vigenère cipher", "year": 1553, "cat": "computing", "wiki": "Vigenère cipher", "req": ["frequency_analysis"], "desc": "A polyalphabetic cipher using a keyword, long considered unbreakable."},
{"id": "logarithm", "name": "Logarithm", "year": 1614, "cat": "computing", "wiki": "Logarithm", "req": ["algebra", "hindu_arabic_numerals"], "desc": "Napier's logarithms turned multiplication into addition and transformed computation."},
{"id": "napiers_bones", "name": "Napier's bones", "year": 1617, "cat": "computing", "wiki": "Napier's bones", "req": ["hindu_arabic_numerals"], "desc": "Numbered rods that reduce multiplication and division to reading and adding digits."},
{"id": "slide_rule", "name": "Slide rule", "year": 1622, "cat": "computing", "wiki": "Slide rule", "req": ["logarithm"], "desc": "An analog calculator of sliding logarithmic scales, the engineer's tool until the 1970s."},
{"id": "mechanical_calculator", "name": "Mechanical calculator", "year": 1623, "cat": "computing", "wiki": "Mechanical calculator", "req": ["gear", "hindu_arabic_numerals"], "desc": "Geared machines that add and subtract automatically, starting with Schickard's calculating clock."},
{"id": "pascaline", "name": "Pascaline", "year": 1642, "cat": "computing", "wiki": "Pascaline", "req": ["mechanical_calculator"], "desc": "Blaise Pascal's geared adding machine with automatic carry."},
{"id": "leibniz_wheel", "name": "Leibniz wheel", "year": 1673, "cat": "computing", "wiki": "Leibniz wheel", "req": ["mechanical_calculator"], "desc": "A stepped drum that lets a calculator multiply by repeated addition."},
{"id": "stepped_reckoner", "name": "Stepped reckoner", "year": 1673, "cat": "computing", "wiki": "Stepped reckoner", "req": ["leibniz_wheel"], "desc": "Leibniz's calculator able to add, subtract, multiply and divide."},
{"id": "binary_number", "name": "Binary number system", "year": 1703, "cat": "computing", "wiki": "Binary number", "req": ["hindu_arabic_numerals", "numerals"], "desc": "Leibniz's base-2 notation using only 0 and 1, the number system of digital computers."},
{"id": "punched_tape", "name": "Punched tape", "year": 1725, "cat": "computing", "wiki": "Punched tape", "req": ["paper", "weaving"], "desc": "Perforated paper strips that store instructions or data, first used to control looms."},
{"id": "arithmometer", "name": "Arithmometer", "year": 1820, "cat": "computing", "wiki": "Arithmometer", "req": ["leibniz_wheel", "machine_tools"], "desc": "Thomas de Colmar's calculator, the first to be mass-produced and sold commercially."},
{"id": "difference_engine", "name": "Difference engine", "year": 1822, "cat": "computing", "wiki": "Difference engine", "req": ["mechanical_calculator", "machine_tools"], "desc": "Babbage's machine for tabulating polynomials by the method of finite differences."},
{"id": "analytical_engine", "name": "Analytical engine", "year": 1837, "cat": "computing", "wiki": "Analytical engine", "req": ["difference_engine", "punched_card"], "desc": "Babbage's design for a general-purpose programmable mechanical computer with a store and mill."},
{"id": "note_g", "name": "Note G", "year": 1843, "cat": "computing", "wiki": "Note G", "req": ["analytical_engine"], "desc": "Ada Lovelace's algorithm for computing Bernoulli numbers, often called the first published program."},
{"id": "tide_predicting_machine", "name": "Tide-predicting machine", "year": 1872, "cat": "computing", "wiki": "Tide-predicting machine", "req": ["gear", "pulley", "calculus", "fourier_analysis"], "desc": "Kelvin's analog machine that summed harmonic components to forecast tides."},
{"id": "ball_and_disk_integrator", "name": "Ball-and-disk integrator", "year": 1876, "cat": "computing", "wiki": "Ball-and-disk integrator", "req": ["gear", "calculus"], "desc": "A mechanical device that integrates continuously, the key part of later analog computers."},
{"id": "one_time_pad", "name": "One-time pad", "year": 1882, "cat": "computing", "wiki": "One-time pad", "req": ["vigenere_cipher", "telegraph"], "desc": "Encryption with a random key as long as the message, provably unbreakable if used correctly."},
{"id": "comptometer", "name": "Comptometer", "year": 1887, "cat": "computing", "wiki": "Comptometer", "req": ["arithmometer"], "desc": "A key-driven adding machine that made rapid office calculation routine."},
{"id": "tabulating_machine", "name": "Tabulating machine", "year": 1890, "cat": "computing", "wiki": "Tabulating machine", "req": ["punched_card", "electromagnet"], "desc": "Hollerith's electromechanical machine that counted punched cards for the 1890 US census."},
{"id": "keypunch", "name": "Keypunch", "year": 1890, "cat": "computing", "wiki": "Keypunch", "req": ["punched_card"], "desc": "A device for punching data into cards, the main data entry method for decades."},
{"id": "unit_record_equipment", "name": "Unit record equipment", "year": 1906, "cat": "computing", "wiki": "Unit record equipment", "req": ["tabulating_machine"], "desc": "Sorters, collators and plugboard tabulators that processed business data on cards."},
{"id": "rotor_machine", "name": "Rotor machine", "year": 1917, "cat": "computing", "wiki": "Rotor machine", "req": ["vigenere_cipher", "electromagnet"], "desc": "Electromechanical ciphers using rotating wired wheels to change the substitution each letter."},
{"id": "enigma_machine", "name": "Enigma machine", "year": 1918, "cat": "computing", "wiki": "Enigma machine", "req": ["rotor_machine"], "desc": "The German rotor cipher machine used widely in the Second World War."},
{"id": "drum_memory", "name": "Drum memory", "year": 1932, "cat": "computing", "wiki": "Drum memory", "req": ["electromagnet", "electric_motor"], "desc": "A rotating magnetic cylinder used as main storage in many early computers."},
{"id": "differential_analyser", "name": "Differential analyser", "year": 1931, "cat": "computing", "wiki": "Differential analyser", "req": ["ball_and_disk_integrator", "electric_motor", "differential_equation"], "desc": "Vannevar Bush's mechanical analog computer for solving differential equations."},
{"id": "turing_machine", "name": "Turing machine", "year": 1936, "cat": "computing", "wiki": "Turing machine", "req": ["boolean_algebra", "incompleteness_theorems"], "desc": "Turing's abstract model of computation that defined what can be computed."},
{"id": "universal_turing_machine", "name": "Universal Turing machine", "year": 1936, "cat": "computing", "wiki": "Universal Turing machine", "req": ["turing_machine"], "desc": "A Turing machine that simulates any other, the theoretical basis of the stored-program computer."},
{"id": "lambda_calculus", "name": "Lambda calculus", "year": 1936, "cat": "computing", "wiki": "Lambda calculus", "req": ["boolean_algebra"], "desc": "Church's formal system of function definition and application, the root of functional programming."},
{"id": "switching_circuit_theory", "name": "Switching circuit theory", "year": 1937, "cat": "computing", "wiki": "Switching circuit theory", "req": ["boolean_algebra", "telephone", "relay"], "desc": "Shannon's use of Boolean algebra to design relay circuits, the basis of digital logic design."},
{"id": "zuse_z1", "name": "Z1", "year": 1938, "cat": "computing", "wiki": "Z1 (computer)", "req": ["binary_number", "mechanical_calculator"], "desc": "Konrad Zuse's mechanical binary computer driven by punched film."},
{"id": "bombe", "name": "Bombe", "year": 1939, "cat": "computing", "wiki": "Bombe", "req": ["enigma_machine", "electromagnet"], "desc": "Electromechanical machine used at Bletchley Park to find Enigma settings."},
{"id": "zuse_z3", "name": "Z3", "year": 1941, "cat": "computing", "wiki": "Z3 (computer)", "req": ["zuse_z1", "electromagnet", "relay"], "desc": "Zuse's relay computer, the first working programmable, fully automatic digital computer."},
{"id": "floating_point", "name": "Floating-point arithmetic", "year": 1941, "cat": "computing", "wiki": "Floating-point arithmetic", "req": ["zuse_z3"], "desc": "Representing numbers with a mantissa and exponent so computers can handle a wide range of values."},
{"id": "atanasoff_berry_computer", "name": "Atanasoff–Berry computer", "year": 1942, "cat": "computing", "wiki": "Atanasoff–Berry computer", "req": ["vacuum_tube", "binary_number", "capacitor"], "desc": "An early electronic digital calculator using vacuum tubes and capacitor memory."},
{"id": "artificial_neuron", "name": "Artificial neuron", "year": 1943, "cat": "computing", "wiki": "Artificial neuron", "req": ["boolean_algebra"], "desc": "McCulloch and Pitts' mathematical model of a neuron as a logic unit."},
{"id": "colossus", "name": "Colossus", "year": 1943, "cat": "computing", "wiki": "Colossus computer", "req": ["vacuum_tube", "punched_tape", "switching_circuit_theory"], "desc": "British codebreaking machines, the first programmable electronic digital computers."},
{"id": "harvard_mark_i", "name": "Harvard Mark I", "year": 1944, "cat": "computing", "wiki": "Harvard Mark I", "req": ["analytical_engine", "unit_record_equipment", "electric_motor", "relay"], "desc": "A large electromechanical computer built by IBM and Aiken, reading instructions from tape."},
{"id": "harvard_architecture", "name": "Harvard architecture", "year": 1944, "cat": "computing", "wiki": "Harvard architecture", "req": ["harvard_mark_i"], "desc": "A design with separate storage and pathways for instructions and data."},
{"id": "eniac", "name": "ENIAC", "year": 1945, "cat": "computing", "wiki": "ENIAC", "req": ["electronic_computer", "vacuum_tube", "atanasoff_berry_computer"], "desc": "The first programmable general-purpose electronic digital computer, built for artillery tables."},
{"id": "von_neumann_architecture", "name": "Von Neumann architecture", "year": 1945, "cat": "computing", "wiki": "Von Neumann architecture", "req": ["eniac", "universal_turing_machine"], "desc": "A design where programs and data share one memory, set out in the EDVAC report."},
{"id": "plankalkul", "name": "Plankalkül", "year": 1945, "cat": "computing", "wiki": "Plankalkül", "req": ["zuse_z3"], "desc": "Zuse's design for the first high-level programming language."},
{"id": "merge_sort", "name": "Merge sort", "year": 1945, "cat": "computing", "wiki": "Merge sort", "req": ["electronic_computer"], "desc": "Von Neumann's divide-and-conquer sorting algorithm."},
{"id": "memex", "name": "Memex", "year": 1945, "cat": "computing", "wiki": "Memex", "req": ["photography"], "desc": "Vannevar Bush's proposed desk for linked microfilm records, inspiring hypertext."},
{"id": "monte_carlo_method", "name": "Monte Carlo method", "year": 1946, "cat": "computing", "wiki": "Monte Carlo method", "req": ["eniac", "probability_theory", "electronic_computer"], "desc": "Solving problems by repeated random sampling, first run on ENIAC for nuclear physics."},
{"id": "simplex_algorithm", "name": "Simplex algorithm", "year": 1947, "cat": "computing", "wiki": "Simplex algorithm", "req": ["algebra", "linear_programming"], "desc": "Dantzig's method for linear programming, a cornerstone of operations research."},
{"id": "williams_tube", "name": "Williams tube", "year": 1947, "cat": "computing", "wiki": "Williams tube", "req": ["cathode_ray_tube"], "desc": "A cathode-ray tube that stored bits as charge spots, the first random-access digital memory."},
{"id": "delay_line_memory", "name": "Delay-line memory", "year": 1947, "cat": "computing", "wiki": "Delay-line memory", "req": ["radar"], "desc": "Memory that stores bits as pulses circulating in mercury or wire, adapted from radar."},
{"id": "assembly_language", "name": "Assembly language", "year": 1947, "cat": "computing", "wiki": "Assembly language", "req": ["von_neumann_architecture"], "desc": "Symbolic notation for machine instructions, translated by an assembler."},
{"id": "stored_program_computer", "name": "Stored-program computer", "year": 1948, "cat": "computing", "wiki": "Stored-program computer", "req": ["von_neumann_architecture", "williams_tube"], "desc": "A computer that holds its program in the same memory as its data."},
{"id": "manchester_baby", "name": "Manchester Baby", "year": 1948, "cat": "computing", "wiki": "Manchester Baby", "req": ["stored_program_computer"], "desc": "The first electronic stored-program computer to run a program."},
{"id": "information_theory", "name": "Information theory", "year": 1948, "cat": "computing", "wiki": "Information theory", "req": ["telegraph", "switching_circuit_theory", "probability_theory", "boolean_algebra"], "desc": "Shannon's mathematical theory of communication, defining the bit and channel capacity."},
{"id": "edsac", "name": "EDSAC", "year": 1949, "cat": "computing", "wiki": "EDSAC", "req": ["von_neumann_architecture", "delay_line_memory"], "desc": "Cambridge's early stored-program computer, the first to give a regular computing service."},
{"id": "edvac", "name": "EDVAC", "year": 1949, "cat": "computing", "wiki": "EDVAC", "req": ["von_neumann_architecture", "delay_line_memory"], "desc": "The binary stored-program computer whose design report defined the von Neumann architecture."},
{"id": "subroutine", "name": "Subroutine", "year": 1949, "cat": "computing", "wiki": "Function (computer programming)", "req": ["assembly_language"], "desc": "A reusable block of code called from elsewhere in a program, introduced on EDSAC."},
{"id": "hamming_code", "name": "Hamming code", "year": 1950, "cat": "computing", "wiki": "Hamming code", "req": ["information_theory"], "desc": "An error-correcting code that detects and fixes single-bit errors."},
{"id": "turing_test", "name": "Turing test", "year": 1950, "cat": "computing", "wiki": "Turing test", "req": ["universal_turing_machine"], "desc": "Turing's proposed test of machine intelligence by conversation."},
{"id": "numerical_weather_prediction", "name": "Numerical weather prediction", "year": 1950, "cat": "computing", "wiki": "Numerical weather prediction", "req": ["eniac", "weather_forecasting", "electronic_computer", "navier_stokes"], "desc": "Forecasting weather by computing equations of the atmosphere, first run on ENIAC."},
{"id": "microcode", "name": "Microcode", "year": 1951, "cat": "computing", "wiki": "Microcode", "req": ["stored_program_computer"], "desc": "Wilkes's layer of low-level instructions that implements a processor's instruction set."},
{"id": "magnetic_tape_storage", "name": "Magnetic-tape data storage", "year": 1951, "cat": "computing", "wiki": "Magnetic-tape data storage", "req": ["electromagnet", "magnetic_tape"], "desc": "Recording digital data on magnetic tape reels, first used with UNIVAC I."},
{"id": "univac_i", "name": "UNIVAC I", "year": 1951, "cat": "computing", "wiki": "UNIVAC I", "req": ["eniac", "magnetic_tape_storage"], "desc": "The first commercial computer produced in the United States."},
{"id": "ferranti_mark_1", "name": "Ferranti Mark 1", "year": 1951, "cat": "computing", "wiki": "Ferranti Mark 1", "req": ["manchester_baby"], "desc": "The first commercially available general-purpose electronic computer."},
{"id": "leo_computer", "name": "LEO", "year": 1951, "cat": "computing", "wiki": "LEO (computer)", "req": ["edsac"], "desc": "The first computer used for routine business data processing."},
{"id": "whirlwind_i", "name": "Whirlwind I", "year": 1951, "cat": "computing", "wiki": "Whirlwind I", "req": ["stored_program_computer", "cathode_ray_tube"], "desc": "An MIT real-time computer that pioneered core memory and interactive displays."},
{"id": "computer_chess", "name": "Computer chess", "year": 1951, "cat": "computing", "wiki": "Computer chess", "req": ["electronic_computer"], "desc": "Programs that play chess, a long-running test bed for AI search."},
{"id": "compiler", "name": "Compiler", "year": 1952, "cat": "computing", "wiki": "Compiler", "req": ["assembly_language"], "desc": "A program that translates a high-level language into machine code."},
{"id": "huffman_coding", "name": "Huffman coding", "year": 1952, "cat": "computing", "wiki": "Huffman coding", "req": ["information_theory"], "desc": "An optimal prefix code for lossless compression."},
{"id": "mainframe_computer", "name": "Mainframe computer", "year": 1952, "cat": "computing", "wiki": "Mainframe computer", "req": ["stored_program_computer", "magnetic_tape_storage"], "desc": "Large central computers for organizations, handling bulk data processing."},
{"id": "speech_recognition", "name": "Speech recognition", "year": 1952, "cat": "computing", "wiki": "Speech recognition", "req": ["vacuum_tube", "telephone"], "desc": "Converting spoken words to text, starting with Bell Labs' digit recognizer."},
{"id": "magnetic_core_memory", "name": "Magnetic-core memory", "year": 1953, "cat": "computing", "wiki": "Magnetic-core memory", "req": ["electromagnet", "stored_program_computer", "ferrite"], "desc": "Tiny magnetic rings storing bits, the dominant main memory for about twenty years."},
{"id": "transistor_computer", "name": "Transistor computer", "year": 1953, "cat": "computing", "wiki": "Transistor computer", "req": ["transistor", "stored_program_computer"], "desc": "Computers using transistors instead of tubes, smaller and more reliable."},
{"id": "hash_table", "name": "Hash table", "year": 1953, "cat": "computing", "wiki": "Hash table", "req": ["electronic_computer"], "desc": "A data structure that finds items by computing their address from a key."},
{"id": "dynamic_programming", "name": "Dynamic programming", "year": 1953, "cat": "computing", "wiki": "Dynamic programming", "req": ["electronic_computer"], "desc": "Bellman's method of solving problems by combining solutions to overlapping subproblems."},
{"id": "natural_language_processing", "name": "Natural language processing", "year": 1954, "cat": "computing", "wiki": "Natural language processing", "req": ["electronic_computer"], "desc": "Computing with human language, starting with the Georgetown machine translation demo."},
{"id": "light_pen", "name": "Light pen", "year": 1955, "cat": "computing", "wiki": "Light pen", "req": ["whirlwind_i"], "desc": "A handheld pointer that selects objects on a CRT display."},
{"id": "operating_system", "name": "Operating system", "year": 1956, "cat": "computing", "wiki": "Operating system", "req": ["mainframe_computer"], "desc": "Software that manages hardware and runs programs, starting with batch monitors."},
{"id": "hard_disk_drive", "name": "Hard disk drive", "year": 1956, "cat": "computing", "wiki": "Hard disk drive", "req": ["drum_memory", "magnetic_tape_storage"], "desc": "Spinning magnetic platters with moving heads for random-access storage, starting with IBM RAMAC."},
{"id": "logic_theorist", "name": "Logic Theorist", "year": 1956, "cat": "computing", "wiki": "Logic Theorist", "req": ["electronic_computer"], "desc": "Newell and Simon's program that proved theorems, often called the first AI program."},
{"id": "finite_element_method", "name": "Finite element method", "year": 1956, "cat": "computing", "wiki": "Finite element method", "req": ["electronic_computer", "beam_theory", "differential_equation"], "desc": "Numerical simulation of structures by dividing them into small elements."},
{"id": "fortran", "name": "Fortran", "year": 1957, "cat": "computing", "wiki": "Fortran", "req": ["compiler"], "desc": "IBM's optimizing compiled language for scientific computing, the first widely used high-level language."},
{"id": "image_scanner", "name": "Image scanner", "year": 1957, "cat": "computing", "wiki": "Image scanner", "req": ["photography", "electronic_computer"], "desc": "A device that digitizes images, first built for the SEAC computer."},
{"id": "computer_music", "name": "Computer music", "year": 1957, "cat": "computing", "wiki": "Computer music", "req": ["electronic_computer"], "desc": "Generating and composing sound with computers, starting with Max Mathews' MUSIC program."},
{"id": "perceptron", "name": "Perceptron", "year": 1958, "cat": "computing", "wiki": "Perceptron", "req": ["artificial_neuron", "electronic_computer"], "desc": "Rosenblatt's trainable linear classifier, the first learning neural network machine."},
{"id": "lisp", "name": "Lisp", "year": 1958, "cat": "computing", "wiki": "Lisp (programming language)", "req": ["lambda_calculus", "compiler"], "desc": "McCarthy's list-processing language, the main language of early AI research."},
{"id": "algol", "name": "ALGOL", "year": 1958, "cat": "computing", "wiki": "ALGOL", "req": ["fortran"], "desc": "An international algorithmic language that introduced block structure and shaped most later languages."},
{"id": "sage_system", "name": "SAGE", "year": 1958, "cat": "computing", "wiki": "Semi-Automatic Ground Environment", "req": ["whirlwind_i", "radar", "modem"], "desc": "A continental air-defense network of computers, radars and displays."},
{"id": "video_game", "name": "Video game", "year": 1958, "cat": "computing", "wiki": "Video game", "req": ["cathode_ray_tube", "electronic_computer"], "desc": "Interactive games played on an electronic display."},
{"id": "cobol", "name": "COBOL", "year": 1959, "cat": "computing", "wiki": "COBOL", "req": ["compiler"], "desc": "A business-oriented language with English-like syntax, still running core banking systems."},
{"id": "machine_learning", "name": "Machine learning", "year": 1959, "cat": "computing", "wiki": "Machine learning", "req": ["artificial_intelligence", "statistics"], "desc": "Programs that improve at tasks from data, named by Arthur Samuel's checkers work."},
{"id": "backus_naur_form", "name": "Backus–Naur form", "year": 1959, "cat": "computing", "wiki": "Backus–Naur form", "req": ["algol"], "desc": "A notation for describing the grammar of programming languages."},
{"id": "garbage_collection", "name": "Garbage collection", "year": 1959, "cat": "computing", "wiki": "Garbage collection (computer science)", "req": ["lisp"], "desc": "Automatic reclaiming of memory a program no longer uses."},
{"id": "quicksort", "name": "Quicksort", "year": 1959, "cat": "computing", "wiki": "Quicksort", "req": ["electronic_computer"], "desc": "Hoare's fast divide-and-conquer sorting algorithm."},
{"id": "dijkstras_algorithm", "name": "Dijkstra's algorithm", "year": 1959, "cat": "computing", "wiki": "Dijkstra's algorithm", "req": ["electronic_computer", "graph_theory"], "desc": "An algorithm for shortest paths in weighted graphs, used in routing."},
{"id": "computer_graphics", "name": "Computer graphics", "year": 1960, "cat": "computing", "wiki": "Computer graphics", "req": ["cathode_ray_tube", "electronic_computer"], "desc": "Creating and displaying images with computers."},
{"id": "time_sharing", "name": "Time-sharing", "year": 1961, "cat": "computing", "wiki": "Time-sharing", "req": ["operating_system", "transistor_computer"], "desc": "Letting many users share one computer interactively, as in MIT's CTSS."},
{"id": "instruction_pipelining", "name": "Instruction pipelining", "year": 1961, "cat": "computing", "wiki": "Instruction pipelining", "req": ["transistor_computer"], "desc": "Overlapping the steps of successive instructions to raise processor throughput."},
{"id": "embedded_system", "name": "Embedded system", "year": 1961, "cat": "computing", "wiki": "Embedded system", "req": ["transistor_computer"], "desc": "A computer built into a larger device to control it."},
{"id": "speech_synthesis", "name": "Speech synthesis", "year": 1961, "cat": "computing", "wiki": "Speech synthesis", "req": ["electronic_computer"], "desc": "Artificial production of speech, first sung by an IBM 704 in 1961."},
{"id": "calculator", "name": "Electronic calculator", "year": 1961, "cat": "computing", "wiki": "Calculator", "req": ["comptometer", "vacuum_tube"], "desc": "An electronic desk calculator, later shrunk to pocket size with integrated circuits."},
{"id": "spacewar", "name": "Spacewar!", "year": 1962, "cat": "computing", "wiki": "Spacewar!", "req": ["video_game", "computer_graphics", "transistor_computer"], "desc": "An early influential computer game written on the PDP-1."},
{"id": "virtual_memory", "name": "Virtual memory", "year": 1962, "cat": "computing", "wiki": "Virtual memory", "req": ["drum_memory", "magnetic_core_memory"], "desc": "Giving programs a large address space backed by slower storage, first on the Atlas."},
{"id": "multiprocessing", "name": "Multiprocessing", "year": 1962, "cat": "computing", "wiki": "Multiprocessing", "req": ["transistor_computer"], "desc": "Using two or more processors in one computer system."},
{"id": "sketchpad", "name": "Sketchpad", "year": 1963, "cat": "computing", "wiki": "Sketchpad", "req": ["light_pen", "computer_graphics", "transistor_computer"], "desc": "Ivan Sutherland's interactive drawing program, ancestor of GUIs and CAD."},
{"id": "computer_aided_design", "name": "Computer-aided design", "year": 1963, "cat": "computing", "wiki": "Computer-aided design", "req": ["sketchpad", "electronic_computer", "cathode_ray_tube"], "desc": "Using computers to create and modify engineering drawings and models."},
{"id": "geographic_information_system", "name": "Geographic information system", "year": 1963, "cat": "computing", "wiki": "Geographic information system", "req": ["computer_graphics", "cartography", "electronic_computer"], "desc": "Systems for storing, analyzing and mapping geographic data."},
{"id": "ascii", "name": "ASCII", "year": 1963, "cat": "computing", "wiki": "ASCII", "req": ["telegraph", "binary_number", "baudot_code"], "desc": "A standard 7-bit character code for text."},
{"id": "ibm_system_360", "name": "IBM System/360", "year": 1964, "cat": "computing", "wiki": "IBM System/360", "req": ["mainframe_computer", "microcode", "transistor_computer"], "desc": "A family of compatible mainframes sharing one instruction set across sizes."},
{"id": "supercomputer", "name": "Supercomputer", "year": 1964, "cat": "computing", "wiki": "Supercomputer", "req": ["transistor_computer"], "desc": "The fastest computers of their time, starting with the CDC 6600."},
{"id": "basic", "name": "BASIC", "year": 1964, "cat": "computing", "wiki": "BASIC", "req": ["fortran", "time_sharing"], "desc": "A simple language designed for students at Dartmouth, later standard on home computers."},
{"id": "database", "name": "Database", "year": 1964, "cat": "computing", "wiki": "Database", "req": ["hard_disk_drive"], "desc": "Organized stored data managed by software, beginning with navigational systems like IDS."},
{"id": "static_ram", "name": "Static random-access memory", "year": 1964, "cat": "computing", "wiki": "Static random-access memory", "req": ["integrated_circuit", "mosfet", "flip_flop"], "desc": "Semiconductor memory holding bits in flip-flops, used for fast caches."},
{"id": "mouse", "name": "Computer mouse", "year": 1964, "cat": "computing", "wiki": "Computer mouse", "req": ["computer_graphics"], "desc": "Engelbart's hand-moved pointing device."},
{"id": "digital_image_processing", "name": "Digital image processing", "year": 1964, "cat": "computing", "wiki": "Digital image processing", "req": ["image_scanner"], "desc": "Algorithms that enhance and analyze digitized images."},
{"id": "minicomputer", "name": "Minicomputer", "year": 1965, "cat": "computing", "wiki": "Minicomputer", "req": ["transistor_computer"], "desc": "Smaller, cheaper computers such as the PDP-8 that brought computing to labs and offices."},
{"id": "expert_system", "name": "Expert system", "year": 1965, "cat": "computing", "wiki": "Expert system", "req": ["lisp", "artificial_intelligence"], "desc": "AI programs encoding specialist rules, beginning with DENDRAL."},
{"id": "fast_fourier_transform", "name": "Fast Fourier transform", "year": 1965, "cat": "computing", "wiki": "Fast Fourier transform", "req": ["electronic_computer", "fourier_analysis"], "desc": "The Cooley–Tukey algorithm for computing Fourier transforms quickly."},
{"id": "multilayer_perceptron", "name": "Multilayer perceptron", "year": 1965, "cat": "computing", "wiki": "Multilayer perceptron", "req": ["perceptron"], "desc": "A neural network with hidden layers, first trained by Ivakhnenko's method."},
{"id": "touchscreen", "name": "Touchscreen", "year": 1965, "cat": "computing", "wiki": "Touchscreen", "req": ["cathode_ray_tube", "capacitor"], "desc": "A display that senses touch as input."},
{"id": "eliza", "name": "ELIZA", "year": 1966, "cat": "computing", "wiki": "ELIZA", "req": ["natural_language_processing", "time_sharing"], "desc": "Weizenbaum's pattern-matching conversation program, the first chatbot."},
{"id": "computer_vision", "name": "Computer vision", "year": 1966, "cat": "computing", "wiki": "Computer vision", "req": ["artificial_intelligence", "digital_image_processing"], "desc": "Giving computers the ability to interpret images and video."},
{"id": "simula", "name": "Simula", "year": 1967, "cat": "computing", "wiki": "Simula", "req": ["algol"], "desc": "The language that introduced classes and objects."},
{"id": "object_oriented_programming", "name": "Object-oriented programming", "year": 1967, "cat": "computing", "wiki": "Object-oriented programming", "req": ["simula"], "desc": "Programming organized around objects that bundle data and behavior."},
{"id": "multics", "name": "Multics", "year": 1967, "cat": "computing", "wiki": "Multics", "req": ["time_sharing"], "desc": "An influential time-sharing system with hierarchical files and security rings."},
{"id": "virtual_machine", "name": "Virtual machine", "year": 1967, "cat": "computing", "wiki": "Virtual machine", "req": ["ibm_system_360", "time_sharing"], "desc": "Software emulation of a whole computer so many systems share one machine."},
{"id": "out_of_order_execution", "name": "Out-of-order execution", "year": 1967, "cat": "computing", "wiki": "Out-of-order execution", "req": ["instruction_pipelining", "ibm_system_360"], "desc": "Tomasulo's method of running instructions as operands become ready."},
{"id": "cpu_cache", "name": "CPU cache", "year": 1968, "cat": "computing", "wiki": "CPU cache", "req": ["ibm_system_360", "static_ram"], "desc": "A small fast memory near the processor that holds recently used data."},
{"id": "structured_programming", "name": "Structured programming", "year": 1968, "cat": "computing", "wiki": "Structured programming", "req": ["algol"], "desc": "A discipline of clear control structures instead of goto statements."},
{"id": "online_system", "name": "NLS", "year": 1968, "cat": "computing", "wiki": "NLS (computer system)", "req": ["mouse", "hypertext", "time_sharing"], "desc": "Engelbart's oN-Line System, shown in the 1968 demo of windows, links and the mouse."},
{"id": "a_star_search", "name": "A* search algorithm", "year": 1968, "cat": "computing", "wiki": "A* search algorithm", "req": ["dijkstras_algorithm", "artificial_intelligence"], "desc": "A heuristic pathfinding algorithm widely used in AI and games."},
{"id": "virtual_reality", "name": "Virtual reality", "year": 1968, "cat": "computing", "wiki": "Virtual reality", "req": ["computer_graphics"], "desc": "Immersive computer-generated environments, starting with Sutherland's head-mounted display."},
{"id": "arpanet", "name": "ARPANET", "year": 1969, "cat": "computing", "wiki": "ARPANET", "req": ["packet_switching", "minicomputer", "modem"], "desc": "The first wide-area packet-switched network, precursor of the internet."},
{"id": "unix", "name": "Unix", "year": 1969, "cat": "computing", "wiki": "Unix", "req": ["multics", "minicomputer"], "desc": "Bell Labs' portable multiuser operating system with a hierarchical file system and pipes."},
{"id": "pascal", "name": "Pascal", "year": 1970, "cat": "computing", "wiki": "Pascal (programming language)", "req": ["algol", "structured_programming"], "desc": "Wirth's language for teaching structured programming."},
{"id": "relational_model", "name": "Relational model", "year": 1970, "cat": "computing", "wiki": "Relational model", "req": ["database", "set_theory"], "desc": "Codd's model of data as tables of rows linked by keys."},
{"id": "dram", "name": "Dynamic random-access memory", "year": 1970, "cat": "computing", "wiki": "Dynamic random-access memory", "req": ["integrated_circuit", "mosfet", "capacitor"], "desc": "Dense semiconductor memory storing bits on capacitors, the main memory of modern computers."},
{"id": "floppy_disk", "name": "Floppy disk", "year": 1971, "cat": "computing", "wiki": "Floppy disk", "req": ["hard_disk_drive"], "desc": "A removable flexible magnetic disk for distributing software and data."},
{"id": "eprom", "name": "EPROM", "year": 1971, "cat": "computing", "wiki": "EPROM", "req": ["integrated_circuit", "floating_gate_mosfet"], "desc": "Erasable programmable read-only memory, cleared with ultraviolet light."},
{"id": "microcontroller", "name": "Microcontroller", "year": 1971, "cat": "computing", "wiki": "Microcontroller", "req": ["microprocessor"], "desc": "A single chip with processor, memory and I/O for control tasks."},
{"id": "file_transfer_protocol", "name": "File Transfer Protocol", "year": 1971, "cat": "computing", "wiki": "File Transfer Protocol", "req": ["arpanet"], "desc": "A standard protocol for transferring files between networked computers."},
{"id": "alohanet", "name": "ALOHAnet", "year": 1971, "cat": "computing", "wiki": "ALOHAnet", "req": ["packet_switching", "radio"], "desc": "A Hawaii radio packet network whose random access method shaped Ethernet."},
{"id": "arcade_video_game", "name": "Arcade video game", "year": 1971, "cat": "computing", "wiki": "Arcade video game", "req": ["video_game", "integrated_circuit"], "desc": "Coin-operated video game machines."},
{"id": "home_video_game_console", "name": "Home video game console", "year": 1972, "cat": "computing", "wiki": "Video game console", "req": ["video_game", "television"], "desc": "A device for playing video games on a home television."},
{"id": "c_language", "name": "C", "year": 1972, "cat": "computing", "wiki": "C (programming language)", "req": ["algol", "unix"], "desc": "Ritchie's systems language for Unix, still the base of most operating systems."},
{"id": "smalltalk", "name": "Smalltalk", "year": 1972, "cat": "computing", "wiki": "Smalltalk", "req": ["object_oriented_programming"], "desc": "A pure object-oriented language and environment from Xerox PARC."},
{"id": "prolog", "name": "Prolog", "year": 1972, "cat": "computing", "wiki": "Prolog", "req": ["lisp"], "desc": "A logic programming language used in AI and natural language work."},
{"id": "version_control", "name": "Version control", "year": 1972, "cat": "computing", "wiki": "Version control", "req": ["unix"], "desc": "Tracking changes to files over time, starting with SCCS."},
{"id": "framebuffer", "name": "Framebuffer", "year": 1972, "cat": "computing", "wiki": "Framebuffer", "req": ["dram", "computer_graphics"], "desc": "Memory holding a full screen of pixels for raster displays."},
{"id": "computer_graphics_3d", "name": "3D computer graphics", "year": 1972, "cat": "computing", "wiki": "3D computer graphics", "req": ["computer_graphics"], "desc": "Rendering three-dimensional models as images."},
{"id": "xerox_alto", "name": "Xerox Alto", "year": 1973, "cat": "computing", "wiki": "Xerox Alto", "req": ["online_system", "framebuffer", "mouse"], "desc": "A PARC workstation with a bitmapped display, mouse and networked GUI."},
{"id": "graphical_user_interface", "name": "Graphical user interface", "year": 1973, "cat": "computing", "wiki": "Graphical user interface", "req": ["xerox_alto"], "desc": "Interacting with computers through windows, icons and pointing rather than typed commands."},
{"id": "wimp", "name": "WIMP", "year": 1973, "cat": "computing", "wiki": "WIMP (computing)", "req": ["graphical_user_interface"], "desc": "The windows, icons, menus and pointer style of interface."},
{"id": "ethernet", "name": "Ethernet", "year": 1973, "cat": "computing", "wiki": "Ethernet", "req": ["alohanet", "packet_switching", "coaxial_cable"], "desc": "A local area network technology that became the standard for wired LANs."},
{"id": "tcp_ip", "name": "TCP/IP", "year": 1974, "cat": "computing", "wiki": "Internet protocol suite", "req": ["arpanet", "packet_switching"], "desc": "Cerf and Kahn's protocols for connecting different networks, the basis of the internet."},
{"id": "sql", "name": "SQL", "year": 1974, "cat": "computing", "wiki": "SQL", "req": ["relational_model"], "desc": "A declarative language for querying and managing relational databases."},
{"id": "cp_m", "name": "CP/M", "year": 1974, "cat": "computing", "wiki": "CP/M", "req": ["microprocessor", "operating_system"], "desc": "An operating system for early microcomputers."},
{"id": "wysiwyg", "name": "WYSIWYG", "year": 1974, "cat": "computing", "wiki": "WYSIWYG", "req": ["xerox_alto"], "desc": "Editing on screen in the same form as the printed result."},
{"id": "texture_mapping", "name": "Texture mapping", "year": 1974, "cat": "computing", "wiki": "Texture mapping", "req": ["computer_graphics_3d"], "desc": "Applying images to 3D surfaces for detail."},
{"id": "vector_processor", "name": "Vector processor", "year": 1974, "cat": "computing", "wiki": "Vector processor", "req": ["supercomputer"], "desc": "A processor that operates on whole arrays of data in one instruction."},
{"id": "discrete_cosine_transform", "name": "Discrete cosine transform", "year": 1974, "cat": "computing", "wiki": "Discrete cosine transform", "req": ["fast_fourier_transform"], "desc": "A transform that concentrates image energy, the core of JPEG and video codecs."},
{"id": "altair_8800", "name": "Altair 8800", "year": 1975, "cat": "computing", "wiki": "Altair 8800", "req": ["microprocessor", "personal_computer"], "desc": "The kit microcomputer that launched the personal computer industry."},
{"id": "data_encryption_standard", "name": "Data Encryption Standard", "year": 1975, "cat": "computing", "wiki": "Data Encryption Standard", "req": ["information_theory", "integrated_circuit"], "desc": "A US standard block cipher for civilian use."},
{"id": "public_key_cryptography", "name": "Public-key cryptography", "year": 1976, "cat": "computing", "wiki": "Public-key cryptography", "req": ["information_theory", "electronic_computer"], "desc": "Encryption using paired public and private keys, so strangers can communicate securely."},
{"id": "diffie_hellman", "name": "Diffie–Hellman key exchange", "year": 1976, "cat": "computing", "wiki": "Diffie–Hellman key exchange", "req": ["public_key_cryptography", "modular_arithmetic"], "desc": "A method for two parties to agree on a secret key over an open channel."},
{"id": "cray_1", "name": "Cray-1", "year": 1976, "cat": "computing", "wiki": "Cray-1", "req": ["vector_processor", "integrated_circuit"], "desc": "Seymour Cray's vector supercomputer, the fastest machine of the late 1970s."},
{"id": "computer_generated_imagery", "name": "Computer-generated imagery", "year": 1976, "cat": "computing", "wiki": "Computer-generated imagery", "req": ["computer_graphics_3d"], "desc": "Computer graphics used in film and television."},
{"id": "word_processor", "name": "Word processor", "year": 1976, "cat": "computing", "wiki": "Word processor", "req": ["personal_computer", "wysiwyg"], "desc": "Software for composing, editing and formatting text."},
{"id": "rsa", "name": "RSA", "year": 1977, "cat": "computing", "wiki": "RSA cryptosystem", "req": ["public_key_cryptography", "modular_arithmetic"], "desc": "The first practical public-key cryptosystem, based on factoring large numbers."},
{"id": "digital_signature", "name": "Digital signature", "year": 1977, "cat": "computing", "wiki": "Digital signature", "req": ["rsa"], "desc": "A cryptographic proof that a message came from its claimed sender unaltered."},
{"id": "apple_ii", "name": "Apple II", "year": 1977, "cat": "computing", "wiki": "Apple II", "req": ["microprocessor", "personal_computer"], "desc": "One of the first mass-market personal computers."},
{"id": "lz_compression", "name": "LZ77 and LZ78", "year": 1977, "cat": "computing", "wiki": "LZ77 and LZ78", "req": ["information_theory"], "desc": "Lempel and Ziv's dictionary compression algorithms, the basis of ZIP and GIF."},
{"id": "x86", "name": "x86", "year": 1978, "cat": "computing", "wiki": "X86", "req": ["microprocessor"], "desc": "Intel's instruction set architecture, dominant in PCs and servers."},
{"id": "bsd", "name": "BSD", "year": 1978, "cat": "computing", "wiki": "Berkeley Software Distribution", "req": ["unix"], "desc": "Berkeley's Unix derivative that added TCP/IP networking and virtual memory."},
{"id": "bulletin_board_system", "name": "Bulletin board system", "year": 1978, "cat": "computing", "wiki": "Bulletin board system", "req": ["modem", "personal_computer"], "desc": "Dial-up computer servers where users posted messages and files."},
{"id": "mud", "name": "MUD", "year": 1978, "cat": "computing", "wiki": "Multi-user dungeon", "req": ["video_game", "time_sharing"], "desc": "A text-based multiplayer virtual world, ancestor of online games."},
{"id": "spreadsheet", "name": "Spreadsheet", "year": 1979, "cat": "computing", "wiki": "Spreadsheet", "req": ["personal_computer"], "desc": "Interactive grids of cells and formulas, beginning with VisiCalc."},
{"id": "relational_database", "name": "Relational database", "year": 1979, "cat": "computing", "wiki": "Relational database", "req": ["relational_model", "sql"], "desc": "Database systems implementing the relational model, starting with Oracle."},
{"id": "ray_tracing", "name": "Ray tracing", "year": 1979, "cat": "computing", "wiki": "Ray tracing (graphics)", "req": ["computer_graphics_3d"], "desc": "Rendering by tracing light rays to produce realistic reflections and shadows."},
{"id": "cryptographic_hash_function", "name": "Cryptographic hash function", "year": 1979, "cat": "computing", "wiki": "Cryptographic hash function", "req": ["hash_table", "information_theory"], "desc": "A one-way function producing a fixed-size digest of any data."},
{"id": "risc", "name": "RISC", "year": 1980, "cat": "computing", "wiki": "Reduced instruction set computer", "req": ["microprocessor", "compiler"], "desc": "Processors with simple fixed-length instructions that run fast with good compilers."},
{"id": "quantum_computing", "name": "Quantum computing", "year": 1980, "cat": "computing", "wiki": "Quantum computing", "req": ["quantum_mechanics", "turing_machine"], "desc": "Computation using superposition and entanglement of qubits."},
{"id": "usenet", "name": "Usenet", "year": 1980, "cat": "computing", "wiki": "Usenet", "req": ["unix", "modem"], "desc": "A worldwide distributed discussion system of newsgroups."},
{"id": "neocognitron", "name": "Neocognitron", "year": 1980, "cat": "computing", "wiki": "Neocognitron", "req": ["multilayer_perceptron"], "desc": "Fukushima's layered network for visual pattern recognition, a forerunner of CNNs."},
{"id": "electronic_design_automation", "name": "Electronic design automation", "year": 1980, "cat": "computing", "wiki": "Electronic design automation", "req": ["computer_aided_design", "integrated_circuit"], "desc": "Software tools for designing integrated circuits."},
{"id": "ibm_pc", "name": "IBM Personal Computer", "year": 1981, "cat": "computing", "wiki": "IBM Personal Computer", "req": ["x86", "personal_computer"], "desc": "IBM's PC, whose open design became the industry standard."},
{"id": "ms_dos", "name": "MS-DOS", "year": 1981, "cat": "computing", "wiki": "MS-DOS", "req": ["cp_m", "x86"], "desc": "Microsoft's disk operating system for IBM PC compatibles."},
{"id": "laptop", "name": "Laptop", "year": 1981, "cat": "computing", "wiki": "Laptop", "req": ["personal_computer"], "desc": "A portable, battery-powered personal computer."},
{"id": "graphics_card", "name": "Graphics card", "year": 1981, "cat": "computing", "wiki": "Graphics card", "req": ["framebuffer", "personal_computer"], "desc": "An expansion card that generates display output."},
{"id": "hopfield_network", "name": "Hopfield network", "year": 1982, "cat": "computing", "wiki": "Hopfield network", "req": ["artificial_neuron", "statistical_mechanics"], "desc": "A recurrent network acting as content-addressable memory."},
{"id": "multi_touch", "name": "Multi-touch", "year": 1982, "cat": "computing", "wiki": "Multi-touch", "req": ["touchscreen"], "desc": "Touch sensing that tracks several contact points at once."},
{"id": "computer_virus", "name": "Computer virus", "year": 1982, "cat": "computing", "wiki": "Computer virus", "req": ["personal_computer"], "desc": "Self-replicating code that spreads by infecting other programs."},
{"id": "domain_name_system", "name": "Domain Name System", "year": 1983, "cat": "computing", "wiki": "Domain Name System", "req": ["tcp_ip"], "desc": "A distributed directory that maps names to internet addresses."},
{"id": "gnu_project", "name": "GNU Project", "year": 1983, "cat": "computing", "wiki": "GNU Project", "req": ["unix"], "desc": "Stallman's project to build a free Unix-like operating system."},
{"id": "macintosh", "name": "Macintosh", "year": 1984, "cat": "computing", "wiki": "Mac (computer)", "req": ["graphical_user_interface", "mouse", "personal_computer"], "desc": "Apple's computer that brought the GUI to a mass market."},
{"id": "postscript", "name": "PostScript", "year": 1984, "cat": "computing", "wiki": "PostScript", "req": ["laser_printer"], "desc": "A page description language that drove laser printers."},
{"id": "flash_memory", "name": "Flash memory", "year": 1984, "cat": "computing", "wiki": "Flash memory", "req": ["eprom", "eeprom"], "desc": "Electrically erasable non-volatile memory in blocks, used in phones and SSDs."},
{"id": "quantum_key_distribution", "name": "Quantum key distribution", "year": 1984, "cat": "computing", "wiki": "Quantum key distribution", "req": ["quantum_mechanics", "one_time_pad", "laser"], "desc": "Sharing encryption keys with quantum states so eavesdropping is detectable."},
{"id": "cplusplus", "name": "C++", "year": 1985, "cat": "computing", "wiki": "C++", "req": ["c_language", "object_oriented_programming"], "desc": "Stroustrup's extension of C with classes and templates."},
{"id": "arm_architecture", "name": "ARM architecture", "year": 1985, "cat": "computing", "wiki": "ARM architecture family", "req": ["risc"], "desc": "A low-power RISC architecture now in nearly all phones."},
{"id": "microsoft_windows", "name": "Microsoft Windows", "year": 1985, "cat": "computing", "wiki": "Microsoft Windows", "req": ["graphical_user_interface", "ms_dos"], "desc": "Microsoft's graphical operating system, dominant on PCs."},
{"id": "cd_rom", "name": "CD-ROM", "year": 1985, "cat": "computing", "wiki": "CD-ROM", "req": ["laser", "compact_disc"], "desc": "Optical discs for distributing software and data."},
{"id": "elliptic_curve_cryptography", "name": "Elliptic-curve cryptography", "year": 1985, "cat": "computing", "wiki": "Elliptic-curve cryptography", "req": ["public_key_cryptography"], "desc": "Public-key cryptography based on elliptic curves, with smaller keys than RSA."},
{"id": "bayesian_network", "name": "Bayesian network", "year": 1985, "cat": "computing", "wiki": "Bayesian network", "req": ["machine_learning", "bayes_theorem"], "desc": "A graphical model of probabilistic dependencies for reasoning under uncertainty."},
{"id": "backpropagation", "name": "Backpropagation", "year": 1986, "cat": "computing", "wiki": "Backpropagation", "req": ["multilayer_perceptron", "calculus"], "desc": "Computing gradients layer by layer to train neural networks."},
{"id": "recurrent_neural_network", "name": "Recurrent neural network", "year": 1986, "cat": "computing", "wiki": "Recurrent neural network", "req": ["backpropagation"], "desc": "Neural networks with loops that process sequences."},
{"id": "sgml", "name": "SGML", "year": 1986, "cat": "computing", "wiki": "Standard Generalized Markup Language", "req": ["ascii"], "desc": "A standard for describing document structure with tags, parent of HTML."},
{"id": "free_software", "name": "Free software", "year": 1986, "cat": "computing", "wiki": "Free software", "req": ["gnu_project"], "desc": "Software users may run, study, change and share, defined by the FSF."},
{"id": "raid", "name": "RAID", "year": 1987, "cat": "computing", "wiki": "RAID", "req": ["hard_disk_drive"], "desc": "Combining multiple disks for redundancy and performance."},
{"id": "computer_worm", "name": "Computer worm", "year": 1988, "cat": "computing", "wiki": "Computer worm", "req": ["internet"], "desc": "Self-propagating malware spreading over networks, notably the Morris worm."},
{"id": "firewall", "name": "Firewall", "year": 1988, "cat": "computing", "wiki": "Firewall (computing)", "req": ["tcp_ip"], "desc": "A system that filters network traffic by security rules."},
{"id": "convolutional_neural_network", "name": "Convolutional neural network", "year": 1989, "cat": "computing", "wiki": "Convolutional neural network", "req": ["backpropagation", "neocognitron"], "desc": "Networks with shared local filters, first trained by LeCun to read digits."},
{"id": "reinforcement_learning", "name": "Reinforcement learning", "year": 1989, "cat": "computing", "wiki": "Reinforcement learning", "req": ["machine_learning", "dynamic_programming"], "desc": "Learning actions by trial and reward, formalized in Q-learning."},
{"id": "gpl", "name": "GNU General Public License", "year": 1989, "cat": "computing", "wiki": "GNU General Public License", "req": ["free_software"], "desc": "A copyleft license requiring derivative software to stay free."},
{"id": "search_engine", "name": "Search engine", "year": 1990, "cat": "computing", "wiki": "Search engine", "req": ["internet", "file_transfer_protocol"], "desc": "Software indexing network content to answer queries, starting with Archie."},
{"id": "linux", "name": "Linux", "year": 1991, "cat": "computing", "wiki": "Linux", "req": ["gnu_project", "unix", "x86"], "desc": "Torvalds' free Unix-like kernel, now running servers, phones and supercomputers."},
{"id": "python", "name": "Python", "year": 1991, "cat": "computing", "wiki": "Python (programming language)", "req": ["c_language"], "desc": "Van Rossum's readable general-purpose language, now central to data science and AI."},
{"id": "http", "name": "HTTP", "year": 1991, "cat": "computing", "wiki": "HTTP", "req": ["tcp_ip", "hypertext"], "desc": "The request-response protocol of the World Wide Web."},
{"id": "html", "name": "HTML", "year": 1991, "cat": "computing", "wiki": "HTML", "req": ["sgml", "hypertext"], "desc": "The markup language for web pages."},
{"id": "web_browser", "name": "Web browser", "year": 1991, "cat": "computing", "wiki": "Web browser", "req": ["world_wide_web", "html"], "desc": "Software for retrieving and displaying web pages."},
{"id": "unicode", "name": "Unicode", "year": 1991, "cat": "computing", "wiki": "Unicode", "req": ["ascii"], "desc": "A universal character set covering the world's writing systems."},
{"id": "solid_state_drive", "name": "Solid-state drive", "year": 1991, "cat": "computing", "wiki": "Solid-state drive", "req": ["flash_memory", "hard_disk_drive"], "desc": "Storage built from flash chips with no moving parts."},
{"id": "pretty_good_privacy", "name": "Pretty Good Privacy", "year": 1991, "cat": "computing", "wiki": "Pretty Good Privacy", "req": ["rsa", "email"], "desc": "Zimmermann's public-key encryption program for email."},
{"id": "augmented_reality", "name": "Augmented reality", "year": 1992, "cat": "computing", "wiki": "Augmented reality", "req": ["virtual_reality"], "desc": "Overlaying computer graphics on a view of the real world."},
{"id": "recommender_system", "name": "Recommender system", "year": 1992, "cat": "computing", "wiki": "Recommender system", "req": ["machine_learning", "email"], "desc": "Systems that suggest items based on user preferences."},
{"id": "mosaic", "name": "Mosaic", "year": 1993, "cat": "computing", "wiki": "NCSA Mosaic", "req": ["web_browser", "graphical_user_interface"], "desc": "The graphical browser that popularized the web."},
{"id": "pdf", "name": "PDF", "year": 1993, "cat": "computing", "wiki": "PDF", "req": ["postscript"], "desc": "Adobe's portable document format."},
{"id": "personal_digital_assistant", "name": "Personal digital assistant", "year": 1993, "cat": "computing", "wiki": "Personal digital assistant", "req": ["microprocessor", "personal_computer"], "desc": "Handheld organizers such as the Apple Newton and Palm Pilot."},
{"id": "secure_hash_algorithms", "name": "SHA", "year": 1993, "cat": "computing", "wiki": "Secure Hash Algorithms", "req": ["cryptographic_hash_function"], "desc": "NIST's family of cryptographic hash functions."},
{"id": "beowulf_cluster", "name": "Beowulf cluster", "year": 1994, "cat": "computing", "wiki": "Beowulf cluster", "req": ["linux", "ethernet"], "desc": "Supercomputing from networks of commodity PCs."},
{"id": "shors_algorithm", "name": "Shor's algorithm", "year": 1994, "cat": "computing", "wiki": "Shor's algorithm", "req": ["quantum_computing", "rsa"], "desc": "A quantum algorithm that factors integers, threatening RSA."},
{"id": "java", "name": "Java", "year": 1995, "cat": "computing", "wiki": "Java (programming language)", "req": ["cplusplus", "garbage_collection"], "desc": "A portable object-oriented language running on a virtual machine."},
{"id": "javascript", "name": "JavaScript", "year": 1995, "cat": "computing", "wiki": "JavaScript", "req": ["web_browser"], "desc": "The scripting language of web pages."},
{"id": "transport_layer_security", "name": "TLS/SSL", "year": 1995, "cat": "computing", "wiki": "Transport Layer Security", "req": ["public_key_cryptography", "world_wide_web"], "desc": "Protocols that encrypt web and other internet traffic."},
{"id": "e_commerce", "name": "E-commerce", "year": 1995, "cat": "computing", "wiki": "E-commerce", "req": ["world_wide_web", "transport_layer_security"], "desc": "Buying and selling goods over the internet."},
{"id": "wiki", "name": "Wiki", "year": 1995, "cat": "computing", "wiki": "Wiki", "req": ["world_wide_web"], "desc": "Websites anyone can edit collaboratively, starting with WikiWikiWeb."},
{"id": "support_vector_machine", "name": "Support vector machine", "year": 1995, "cat": "computing", "wiki": "Support vector machine", "req": ["machine_learning"], "desc": "A classifier finding maximum-margin boundaries between classes."},
{"id": "quantum_error_correction", "name": "Quantum error correction", "year": 1995, "cat": "computing", "wiki": "Quantum error correction", "req": ["quantum_computing"], "desc": "Protecting quantum information from noise by encoding it across many qubits."},
{"id": "trapped_ion_qc", "name": "Trapped-ion quantum computer", "year": 1995, "cat": "computing", "wiki": "Trapped-ion quantum computer", "req": ["quantum_computing", "laser"], "desc": "Quantum computers using ions held in electromagnetic traps as qubits."},
{"id": "usb", "name": "USB", "year": 1996, "cat": "computing", "wiki": "USB", "req": ["personal_computer"], "desc": "A standard serial bus for connecting peripherals."},
{"id": "css", "name": "CSS", "year": 1996, "cat": "computing", "wiki": "CSS", "req": ["html"], "desc": "Style sheets that separate web page presentation from content."},
{"id": "mobile_operating_system", "name": "Mobile operating system", "year": 1996, "cat": "computing", "wiki": "Mobile operating system", "req": ["personal_digital_assistant", "operating_system"], "desc": "Operating systems designed for handheld devices."},
{"id": "deep_blue", "name": "Deep Blue", "year": 1997, "cat": "computing", "wiki": "Deep Blue (chess computer)", "req": ["computer_chess", "supercomputer"], "desc": "IBM's chess computer that beat world champion Kasparov."},
{"id": "long_short_term_memory", "name": "LSTM", "year": 1997, "cat": "computing", "wiki": "Long short-term memory", "req": ["recurrent_neural_network"], "desc": "A recurrent network with gated memory cells that learns long-range patterns."},
{"id": "social_media", "name": "Social media", "year": 1997, "cat": "computing", "wiki": "Social media", "req": ["world_wide_web"], "desc": "Online platforms for sharing content and connections among users."},
{"id": "hashcash", "name": "Hashcash", "year": 1997, "cat": "computing", "wiki": "Hashcash", "req": ["cryptographic_hash_function"], "desc": "A proof-of-work scheme to deter spam, later used in Bitcoin mining."},
{"id": "open_source_software", "name": "Open-source software", "year": 1998, "cat": "computing", "wiki": "Open-source software", "req": ["free_software", "linux"], "desc": "Software developed with publicly available source code under open licenses."},
{"id": "pagerank", "name": "PageRank", "year": 1998, "cat": "computing", "wiki": "PageRank", "req": ["search_engine", "world_wide_web", "graph_theory", "matrix"], "desc": "Google's link-analysis ranking algorithm for web search."},
{"id": "graphics_processing_unit", "name": "GPU", "year": 1999, "cat": "computing", "wiki": "Graphics processing unit", "req": ["graphics_card", "computer_graphics_3d", "texture_mapping"], "desc": "A specialized parallel processor for rendering graphics."},
{"id": "peer_to_peer", "name": "Peer-to-peer", "year": 1999, "cat": "computing", "wiki": "Peer-to-peer", "req": ["internet"], "desc": "Networks where computers share resources directly without central servers."},
{"id": "internet_of_things", "name": "Internet of things", "year": 1999, "cat": "computing", "wiki": "Internet of things", "req": ["internet", "microcontroller"], "desc": "Everyday objects networked with sensors and controls."},
{"id": "software_as_a_service", "name": "Software as a service", "year": 1999, "cat": "computing", "wiki": "Software as a service", "req": ["world_wide_web"], "desc": "Applications delivered over the web on subscription."},
{"id": "superconducting_qc", "name": "Superconducting quantum computing", "year": 1999, "cat": "computing", "wiki": "Superconducting quantum computing", "req": ["quantum_computing", "superconductivity"], "desc": "Quantum processors built from superconducting circuits."},
{"id": "usb_flash_drive", "name": "USB flash drive", "year": 2000, "cat": "computing", "wiki": "USB flash drive", "req": ["flash_memory", "usb"], "desc": "A pocket storage device of flash memory."},
{"id": "os_level_virtualization", "name": "OS-level virtualization", "year": 2000, "cat": "computing", "wiki": "OS-level virtualization", "req": ["virtual_machine", "unix"], "desc": "Isolating applications in containers that share one OS kernel."},
{"id": "multi_core_processor", "name": "Multi-core processor", "year": 2001, "cat": "computing", "wiki": "Multi-core processor", "req": ["microprocessor", "multiprocessing"], "desc": "A chip with several processor cores."},
{"id": "advanced_encryption_standard", "name": "AES", "year": 2001, "cat": "computing", "wiki": "Advanced Encryption Standard", "req": ["data_encryption_standard"], "desc": "The Rijndael block cipher, the global standard for symmetric encryption."},
{"id": "gpgpu", "name": "GPGPU", "year": 2001, "cat": "computing", "wiki": "General-purpose computing on graphics processing units", "req": ["graphics_processing_unit"], "desc": "Using graphics processors for non-graphics computation."},
{"id": "wikipedia", "name": "Wikipedia", "year": 2001, "cat": "computing", "wiki": "Wikipedia", "req": ["wiki", "encyclopedia", "world_wide_web"], "desc": "A free online encyclopedia written collaboratively."},
{"id": "mapreduce", "name": "MapReduce", "year": 2004, "cat": "computing", "wiki": "MapReduce", "req": ["lisp", "beowulf_cluster"], "desc": "Google's model for processing huge datasets across clusters."},
{"id": "git", "name": "Git", "year": 2005, "cat": "computing", "wiki": "Git", "req": ["version_control", "linux"], "desc": "A distributed version control system written for Linux development."},
{"id": "ajax", "name": "Ajax", "year": 2005, "cat": "computing", "wiki": "Ajax (programming)", "req": ["javascript"], "desc": "Updating web pages asynchronously, enabling interactive web apps."},
{"id": "deep_learning", "name": "Deep learning", "year": 2006, "cat": "computing", "wiki": "Deep learning", "req": ["backpropagation", "convolutional_neural_network"], "desc": "Training neural networks with many layers on large data."},
{"id": "cloud_computing", "name": "Cloud computing", "year": 2006, "cat": "computing", "wiki": "Cloud computing", "req": ["virtual_machine", "internet", "software_as_a_service"], "desc": "On-demand rented computing and storage over the internet."},
{"id": "apache_hadoop", "name": "Hadoop", "year": 2006, "cat": "computing", "wiki": "Apache Hadoop", "req": ["mapreduce", "open_source_software"], "desc": "An open-source framework for distributed storage and processing."},
{"id": "monte_carlo_tree_search", "name": "Monte Carlo tree search", "year": 2006, "cat": "computing", "wiki": "Monte Carlo tree search", "req": ["monte_carlo_method", "artificial_intelligence"], "desc": "Game-tree search guided by random playouts."},
{"id": "cuda", "name": "CUDA", "year": 2007, "cat": "computing", "wiki": "CUDA", "req": ["gpgpu"], "desc": "Nvidia's platform for programming GPUs in C-like code."},
{"id": "ios", "name": "iOS", "year": 2007, "cat": "computing", "wiki": "IOS", "req": ["mobile_operating_system", "bsd", "multi_touch"], "desc": "Apple's mobile operating system for the iPhone."},
{"id": "android", "name": "Android", "year": 2008, "cat": "computing", "wiki": "Android (operating system)", "req": ["linux", "mobile_operating_system", "java"], "desc": "Google's open-source mobile OS, the most widely used."},
{"id": "app_store", "name": "App store", "year": 2008, "cat": "computing", "wiki": "App store", "req": ["smartphone", "e_commerce"], "desc": "Digital marketplaces for mobile applications."},
{"id": "blockchain", "name": "Blockchain", "year": 2008, "cat": "computing", "wiki": "Blockchain", "req": ["cryptographic_hash_function", "peer_to_peer", "digital_signature"], "desc": "An append-only ledger of hash-linked blocks kept by many nodes."},
{"id": "bitcoin", "name": "Bitcoin", "year": 2009, "cat": "computing", "wiki": "Bitcoin", "req": ["blockchain", "hashcash"], "desc": "The first decentralized cryptocurrency."},
{"id": "imagenet", "name": "ImageNet", "year": 2009, "cat": "computing", "wiki": "ImageNet", "req": ["world_wide_web", "machine_learning"], "desc": "A large labeled image dataset that drove progress in computer vision."},
{"id": "nosql", "name": "NoSQL", "year": 2009, "cat": "computing", "wiki": "NoSQL", "req": ["relational_database", "mapreduce"], "desc": "Non-relational databases for scale and flexible data."},
{"id": "go_language", "name": "Go", "year": 2009, "cat": "computing", "wiki": "Go (programming language)", "req": ["c_language"], "desc": "Google's compiled language for concurrent server software."},
{"id": "tablet_computer", "name": "Tablet computer", "year": 2010, "cat": "computing", "wiki": "Tablet computer", "req": ["multi_touch", "mobile_operating_system", "lithium_ion_battery"], "desc": "A flat touchscreen mobile computer."},
{"id": "risc_v", "name": "RISC-V", "year": 2010, "cat": "computing", "wiki": "RISC-V", "req": ["risc", "open_source_software"], "desc": "An open, royalty-free instruction set architecture."},
{"id": "virtual_assistant", "name": "Virtual assistant", "year": 2011, "cat": "computing", "wiki": "Virtual assistant", "req": ["speech_recognition", "smartphone", "natural_language_processing"], "desc": "Voice-driven software agents such as Siri."},
{"id": "ibm_watson", "name": "IBM Watson", "year": 2011, "cat": "computing", "wiki": "IBM Watson", "req": ["natural_language_processing", "supercomputer"], "desc": "A question-answering system that won Jeopardy!."},
{"id": "alexnet", "name": "AlexNet", "year": 2012, "cat": "computing", "wiki": "AlexNet", "req": ["imagenet", "convolutional_neural_network", "cuda", "deep_learning"], "desc": "A GPU-trained CNN whose ImageNet win started the deep learning boom."},
{"id": "docker", "name": "Docker", "year": 2013, "cat": "computing", "wiki": "Docker (software)", "req": ["os_level_virtualization", "linux"], "desc": "A tool for packaging and running software in containers."},
{"id": "word2vec", "name": "Word2vec", "year": 2013, "cat": "computing", "wiki": "Word2Vec", "req": ["deep_learning", "natural_language_processing"], "desc": "Learning vector embeddings of words from text."},
{"id": "deep_reinforcement_learning", "name": "Deep reinforcement learning", "year": 2013, "cat": "computing", "wiki": "Deep reinforcement learning", "req": ["reinforcement_learning", "deep_learning"], "desc": "Combining deep networks with RL, shown by DQN on Atari games."},
{"id": "generative_adversarial_network", "name": "GAN", "year": 2014, "cat": "computing", "wiki": "Generative adversarial network", "req": ["deep_learning"], "desc": "Two competing networks that learn to generate realistic data."},
{"id": "seq2seq", "name": "Seq2seq", "year": 2014, "cat": "computing", "wiki": "Seq2seq", "req": ["long_short_term_memory", "deep_learning"], "desc": "Encoder-decoder networks mapping one sequence to another, as in translation."},
{"id": "attention_mechanism", "name": "Attention", "year": 2014, "cat": "computing", "wiki": "Attention (machine learning)", "req": ["seq2seq"], "desc": "Letting networks weight relevant parts of their input."},
{"id": "kubernetes", "name": "Kubernetes", "year": 2014, "cat": "computing", "wiki": "Kubernetes", "req": ["docker", "cloud_computing"], "desc": "An open-source system for orchestrating containers."},
{"id": "diffusion_model", "name": "Diffusion model", "year": 2015, "cat": "computing", "wiki": "Diffusion model", "req": ["deep_learning"], "desc": "Generative models that learn to reverse a noising process."},
{"id": "residual_neural_network", "name": "ResNet", "year": 2015, "cat": "computing", "wiki": "Residual neural network", "req": ["convolutional_neural_network"], "desc": "Very deep networks trained with skip connections."},
{"id": "rust", "name": "Rust", "year": 2015, "cat": "computing", "wiki": "Rust (programming language)", "req": ["cplusplus"], "desc": "A systems language with memory safety without garbage collection."},
{"id": "ethereum", "name": "Ethereum", "year": 2015, "cat": "computing", "wiki": "Ethereum", "req": ["bitcoin"], "desc": "A blockchain platform for programmable smart contracts."},
{"id": "tensor_processing_unit", "name": "TPU", "year": 2016, "cat": "computing", "wiki": "Tensor Processing Unit", "req": ["deep_learning", "integrated_circuit"], "desc": "Google's custom chip for neural network computation."},
{"id": "alphago", "name": "AlphaGo", "year": 2016, "cat": "computing", "wiki": "AlphaGo", "req": ["deep_reinforcement_learning", "monte_carlo_tree_search", "convolutional_neural_network"], "desc": "DeepMind's program that beat a top professional at Go."},
{"id": "wavenet", "name": "WaveNet", "year": 2016, "cat": "computing", "wiki": "WaveNet", "req": ["convolutional_neural_network", "speech_synthesis"], "desc": "A neural network generating realistic speech audio."},
{"id": "transformer_architecture", "name": "Transformer", "year": 2017, "cat": "computing", "wiki": "Transformer (deep learning)", "req": ["attention_mechanism"], "desc": "A network built on self-attention that became the basis of modern language models."},
{"id": "alphazero", "name": "AlphaZero", "year": 2017, "cat": "computing", "wiki": "AlphaZero", "req": ["alphago"], "desc": "A program that mastered chess, shogi and Go from self-play alone."},
{"id": "rlhf", "name": "RLHF", "year": 2017, "cat": "computing", "wiki": "Reinforcement learning from human feedback", "req": ["deep_reinforcement_learning"], "desc": "Training models with rewards learned from human preferences."},
{"id": "neural_processing_unit", "name": "Neural processing unit", "year": 2017, "cat": "computing", "wiki": "Neural processing unit", "req": ["tensor_processing_unit", "smartphone"], "desc": "On-device AI accelerators in phones and PCs."},
{"id": "generative_pretrained_transformer", "name": "GPT", "year": 2018, "cat": "computing", "wiki": "Generative pre-trained transformer", "req": ["transformer_architecture"], "desc": "Transformer models pretrained to predict text and then adapted."},
{"id": "bert", "name": "BERT", "year": 2018, "cat": "computing", "wiki": "BERT (language model)", "req": ["transformer_architecture"], "desc": "A bidirectional transformer pretrained for language understanding."},
{"id": "quantum_supremacy", "name": "Quantum supremacy", "year": 2019, "cat": "computing", "wiki": "Quantum supremacy", "req": ["superconducting_qc"], "desc": "A quantum computer performing a task beyond classical computers."},
{"id": "large_language_model", "name": "Large language model", "year": 2020, "cat": "computing", "wiki": "Large language model", "req": ["generative_pretrained_transformer", "gpgpu"], "desc": "Very large transformer models trained on vast text, such as GPT-3."},
{"id": "retrieval_augmented_generation", "name": "Retrieval-augmented generation", "year": 2020, "cat": "computing", "wiki": "Retrieval-augmented generation", "req": ["large_language_model", "search_engine"], "desc": "Grounding language model output in retrieved documents."},
{"id": "vision_transformer", "name": "Vision transformer", "year": 2020, "cat": "computing", "wiki": "Vision transformer", "req": ["transformer_architecture"], "desc": "Transformers applied to image patches."},
{"id": "text_to_image_model", "name": "Text-to-image model", "year": 2021, "cat": "computing", "wiki": "Text-to-image model", "req": ["diffusion_model", "transformer_architecture"], "desc": "Models generating images from text descriptions."},
{"id": "chatgpt", "name": "ChatGPT", "year": 2022, "cat": "computing", "wiki": "ChatGPT", "req": ["large_language_model", "rlhf"], "desc": "OpenAI's chatbot that brought LLMs to the mass market."},
{"id": "generative_ai", "name": "Generative AI", "year": 2022, "cat": "computing", "wiki": "Generative AI", "req": ["large_language_model", "text_to_image_model"], "desc": "AI that produces new text, images, audio and video."},
{"id": "text_to_video_model", "name": "Text-to-video model", "year": 2022, "cat": "computing", "wiki": "Text-to-video model", "req": ["text_to_image_model"], "desc": "Models generating video from text."},
{"id": "exascale_computing", "name": "Exascale computing", "year": 2022, "cat": "computing", "wiki": "Exascale computing", "req": ["supercomputer", "gpgpu"], "desc": "Supercomputers performing a quintillion operations per second."},
{"id": "post_quantum_cryptography", "name": "Post-quantum cryptography", "year": 2022, "cat": "computing", "wiki": "Post-quantum cryptography", "req": ["shors_algorithm", "public_key_cryptography"], "desc": "Cryptography designed to resist quantum attacks."},
{"id": "reasoning_model", "name": "Reasoning model", "year": 2024, "cat": "computing", "wiki": "Reasoning model", "req": ["large_language_model", "rlhf"], "desc": "LLMs trained to work through problems step by step before answering."},
{"id": "ai_agent", "name": "AI agent", "year": 2024, "cat": "computing", "wiki": "AI agent", "req": ["large_language_model"], "desc": "LLM-driven systems that plan and use tools to carry out multistep tasks."},
{"id": "pit_house", "name": "Pit house", "year": -15000, "cat": "construction", "wiki": "Pit-house", "req": ["stone_tools"], "desc": "A dwelling dug partly into the ground and roofed with timber, bone or turf, using the earth for insulation."},
{"id": "megalith", "name": "Megalith", "year": -9500, "cat": "construction", "wiki": "Megalith", "req": ["stone_tools", "cordage"], "desc": "Monuments of huge raised stones, from Gobekli Tepe onward, showing early mastery of moving heavy loads."},
{"id": "gobekli_tepe", "name": "Gobekli Tepe", "year": -9500, "cat": "construction", "wiki": "Göbekli Tepe", "req": ["megalith"], "desc": "Monumental enclosures of carved T-shaped stone pillars, the oldest known megalithic site."},
{"id": "thatching", "name": "Thatching", "year": -7000, "cat": "construction", "wiki": "Thatching", "req": ["agriculture"], "desc": "Roofing with layered straw, reed or grass that sheds rain and insulates."},
{"id": "wattle_and_daub", "name": "Wattle and daub", "year": -6000, "cat": "construction", "wiki": "Wattle and daub", "req": ["weaving", "agriculture"], "desc": "Woven wooden lattice walls daubed with clay, dung and straw; a building method used for millennia."},
{"id": "longhouse", "name": "Longhouse", "year": -5500, "cat": "construction", "wiki": "Longhouse", "req": ["wattle_and_daub", "thatching"], "desc": "Long timber-post dwellings of early farming villages that housed extended families and livestock."},
{"id": "stilt_house", "name": "Stilt house", "year": -5000, "cat": "construction", "wiki": "Stilt house", "req": ["stone_tools"], "desc": "Houses raised on piles over water or soft ground, protecting against floods and pests."},
{"id": "mortise_and_tenon", "name": "Mortise and tenon", "year": -5000, "cat": "construction", "wiki": "Mortise and tenon", "req": ["stone_tools"], "desc": "A wood joint where a projecting tenon fits a cut socket, the basis of all timber joinery."},
{"id": "rammed_earth", "name": "Rammed earth", "year": -5000, "cat": "construction", "wiki": "Rammed earth", "req": ["mudbrick"], "desc": "Damp earth compacted in layers inside formwork to make thick, durable walls."},
{"id": "cistern", "name": "Cistern", "year": -4000, "cat": "construction", "wiki": "Cistern", "req": ["lime_mortar"], "desc": "A sealed underground tank for storing rainwater, made watertight with lime plaster."},
{"id": "megalithic_dolmen", "name": "Dolmen", "year": -4000, "cat": "construction", "wiki": "Dolmen", "req": ["megalith"], "desc": "A chamber tomb of upright stones capped by a large flat stone, an early spanning structure."},
{"id": "dry_stone", "name": "Dry stone walling", "year": -3500, "cat": "construction", "wiki": "Dry stone", "req": ["stone_tools"], "desc": "Building walls from fitted stones without mortar, used for houses, terraces and enclosures."},
{"id": "fired_brick", "name": "Fired brick", "year": -3500, "cat": "construction", "wiki": "Brick", "req": ["mudbrick", "kiln"], "desc": "Kiln-baked clay bricks that resist water far better than sun-dried mudbrick."},
{"id": "corbel_arch", "name": "Corbel arch", "year": -3200, "cat": "construction", "wiki": "Corbel arch", "req": ["dry_stone"], "desc": "A span made by stepping courses of stone inward until they meet, used in tombs and early vaults."},
{"id": "mastaba", "name": "Mastaba", "year": -3100, "cat": "construction", "wiki": "Mastaba", "req": ["mudbrick"], "desc": "A flat-roofed rectangular Egyptian tomb of mudbrick or stone, the forerunner of the pyramid."},
{"id": "post_and_lintel", "name": "Post and lintel", "year": -3000, "cat": "construction", "wiki": "Post and lintel", "req": ["megalith"], "desc": "A horizontal beam carried on two upright posts, the simplest structural span."},
{"id": "levee", "name": "Levee", "year": -3000, "cat": "construction", "wiki": "Levee", "req": ["irrigation"], "desc": "An earthen embankment along a river that holds back floodwater from fields and towns."},
{"id": "embankment_dam", "name": "Embankment dam", "year": -3000, "cat": "construction", "wiki": "Embankment dam", "req": ["irrigation"], "desc": "A dam of compacted earth or rock fill; the oldest dam type, as at Jawa in Jordan."},
{"id": "ashlar", "name": "Ashlar masonry", "year": -2700, "cat": "construction", "wiki": "Ashlar", "req": ["smelting", "stone_tools"], "desc": "Finely dressed rectangular stone blocks laid in regular courses with thin joints."},
{"id": "gravity_dam", "name": "Gravity dam", "year": -2650, "cat": "construction", "wiki": "Gravity dam", "req": ["embankment_dam", "ashlar"], "desc": "A massive masonry or concrete dam that resists water pressure by its own weight."},
{"id": "pyramid_construction", "name": "Pyramid construction", "year": -2630, "cat": "construction", "wiki": "Construction of the Egyptian pyramids", "req": ["mastaba", "ashlar", "lever", "surveying", "sledge"], "desc": "Quarrying, hauling and stacking millions of stone blocks with ramps and levers to build Egypt's pyramids."},
{"id": "column", "name": "Column", "year": -2600, "cat": "construction", "wiki": "Column", "req": ["ashlar"], "desc": "A vertical structural member carrying beams or arches, first carved in stone in Egypt."},
{"id": "plumb_bob", "name": "Plumb bob", "year": -2600, "cat": "construction", "wiki": "Plumb bob", "req": ["cordage"], "desc": "A weight hung on a string to establish a true vertical when building walls."},
{"id": "great_pyramid", "name": "Great Pyramid of Giza", "year": -2560, "cat": "construction", "wiki": "Great Pyramid of Giza", "req": ["pyramid_construction", "surveying", "inclined_plane"], "desc": "Khufu's pyramid, the tallest human-made structure for nearly four millennia."},
{"id": "rock_cut_architecture", "name": "Rock-cut architecture", "year": -2500, "cat": "construction", "wiki": "Rock-cut architecture", "req": ["smelting", "stone_tools"], "desc": "Carving tombs, temples and dwellings directly out of solid rock."},
{"id": "true_arch", "name": "Arch", "year": -2500, "cat": "construction", "wiki": "Arch", "req": ["mudbrick"], "desc": "A curved span of wedge-shaped units held in compression, carrying loads far wider than a lintel."},
{"id": "stonehenge", "name": "Stonehenge", "year": -2500, "cat": "construction", "wiki": "Stonehenge", "req": ["post_and_lintel"], "desc": "A Neolithic ring of sarsen uprights capped with lintels joined by woodworking-style joints."},
{"id": "ziggurat", "name": "Ziggurat", "year": -2100, "cat": "construction", "wiki": "Ziggurat", "req": ["mudbrick", "fired_brick"], "desc": "A Mesopotamian stepped temple tower of mudbrick faced with baked brick."},
{"id": "barrel_vault", "name": "Barrel vault", "year": -2000, "cat": "construction", "wiki": "Barrel vault", "req": ["true_arch"], "desc": "An arch extended along its length to roof a long space."},
{"id": "log_building", "name": "Log building", "year": -2000, "cat": "construction", "wiki": "Log building", "req": ["stone_tools"], "desc": "Walls of horizontal logs notched together at the corners, typical of forested northern regions."},
{"id": "building_code", "name": "Building code", "year": -1754, "cat": "construction", "wiki": "Building code", "req": ["writing"], "desc": "Rules setting standards for building safety, first recorded in the Code of Hammurabi."},
{"id": "tholos_tomb", "name": "Beehive tomb", "year": -1500, "cat": "construction", "wiki": "Beehive tomb", "req": ["corbel_arch"], "desc": "A Mycenaean tholos tomb roofed with a corbelled stone dome."},
{"id": "cyclopean_masonry", "name": "Cyclopean masonry", "year": -1350, "cat": "construction", "wiki": "Cyclopean masonry", "req": ["dry_stone"], "desc": "Massive unworked limestone boulders fitted together without mortar, as at Mycenae."},
{"id": "windcatcher", "name": "Windcatcher", "year": -1300, "cat": "construction", "wiki": "Windcatcher", "req": ["mudbrick"], "desc": "A tower that catches wind and drives it through a building for passive cooling and ventilation."},
{"id": "treasury_of_atreus", "name": "Treasury of Atreus", "year": -1250, "cat": "construction", "wiki": "Treasury of Atreus", "req": ["tholos_tomb"], "desc": "A Mycenaean tholos whose corbelled dome was the widest in the world for over a millennium."},
{"id": "roof_tiles", "name": "Roof tiles", "year": -1000, "cat": "construction", "wiki": "Roof tiles", "req": ["kiln"], "desc": "Fired clay tiles laid in overlapping rows to make a durable, fireproof roof."},
{"id": "siloam_tunnel", "name": "Siloam tunnel", "year": -700, "cat": "construction", "wiki": "Siloam tunnel", "req": ["iron_working", "cistern", "surveying"], "desc": "A water tunnel cut through rock under Jerusalem by two teams digging from opposite ends."},
{"id": "aqueduct", "name": "Aqueduct", "year": -690, "cat": "construction", "wiki": "Aqueduct (water supply)", "req": ["irrigation", "ashlar", "surveying"], "desc": "A built channel carrying water by gravity over long distances to a city."},
{"id": "classical_order", "name": "Classical order", "year": -600, "cat": "construction", "wiki": "Classical order", "req": ["column", "post_and_lintel"], "desc": "The Doric, Ionic and Corinthian systems of proportioned columns and entablatures."},
{"id": "tunnel_of_eupalinos", "name": "Tunnel of Eupalinos", "year": -530, "cat": "construction", "wiki": "Tunnel of Eupalinos", "req": ["aqueduct", "iron_working", "surveying"], "desc": "A 1 km aqueduct tunnel on Samos dug from both ends with geometric surveying."},
{"id": "crane_machine", "name": "Crane", "year": -515, "cat": "construction", "wiki": "Crane (machine)", "req": ["pulley", "lever"], "desc": "A lifting machine using pulleys and a jib, first used by Greek builders to raise stone blocks."},
{"id": "timber_framing", "name": "Timber framing", "year": -500, "cat": "construction", "wiki": "Timber framing", "req": ["mortise_and_tenon", "iron_working"], "desc": "A structural skeleton of heavy squared timbers joined with pegged joints, infilled between."},
{"id": "pontoon_bridge", "name": "Pontoon bridge", "year": -480, "cat": "construction", "wiki": "Pontoon bridge", "req": ["dugout_canoe", "cordage"], "desc": "A floating bridge of boats lashed together and decked over."},
{"id": "parthenon", "name": "Parthenon", "year": -438, "cat": "construction", "wiki": "Parthenon", "req": ["classical_order"], "desc": "The Doric marble temple of Athens, a model of refined proportion and optical correction."},
{"id": "dougong", "name": "Dougong", "year": -400, "cat": "construction", "wiki": "Dougong", "req": ["timber_framing"], "desc": "Interlocking wooden bracket sets that carry the wide eaves of Chinese timber buildings."},
{"id": "roman_aqueduct", "name": "Roman aqueduct", "year": -312, "cat": "construction", "wiki": "Roman aqueduct", "req": ["aqueduct", "true_arch", "lime_mortar"], "desc": "Graded channels on arcades and tunnels that supplied Roman cities with abundant water."},
{"id": "lighthouse", "name": "Lighthouse", "year": -280, "cat": "construction", "wiki": "Lighthouse", "req": ["ashlar"], "desc": "A tower with a light to guide ships, beginning with the Pharos of Alexandria."},
{"id": "arch_bridge", "name": "Arch bridge", "year": -200, "cat": "construction", "wiki": "Arch bridge", "req": ["true_arch", "ashlar"], "desc": "A bridge carried on masonry arches, perfected by Roman engineers."},
{"id": "inverted_siphon", "name": "Inverted siphon", "year": -200, "cat": "construction", "wiki": "Siphon", "req": ["roman_aqueduct"], "desc": "A sealed pipe that carries water down and across a valley and back up by pressure."},
{"id": "formwork", "name": "Formwork", "year": -200, "cat": "construction", "wiki": "Formwork", "req": ["roman_concrete"], "desc": "Temporary moulds that hold wet concrete in shape until it sets."},
{"id": "insula_building", "name": "Insula", "year": -200, "cat": "construction", "wiki": "Insula (building)", "req": ["fired_brick", "roman_concrete"], "desc": "Multi-storey Roman apartment blocks of brick-faced concrete housing most urban residents."},
{"id": "dome", "name": "Dome", "year": -100, "cat": "construction", "wiki": "Dome", "req": ["true_arch", "roman_concrete"], "desc": "A hemispherical vault, an arch rotated about its axis, enclosing large spaces without columns."},
{"id": "groin_vault", "name": "Groin vault", "year": -100, "cat": "construction", "wiki": "Groin vault", "req": ["barrel_vault", "roman_concrete"], "desc": "Two barrel vaults crossing at right angles, concentrating loads onto corner piers."},
{"id": "hypocaust", "name": "Hypocaust", "year": -100, "cat": "construction", "wiki": "Hypocaust", "req": ["fired_brick", "control_of_fire", "lime_mortar"], "desc": "Roman underfloor heating that drew hot furnace gases through spaces under floors and walls."},
{"id": "arch_dam", "name": "Arch dam", "year": -100, "cat": "construction", "wiki": "Arch dam", "req": ["true_arch", "gravity_dam"], "desc": "A dam curved upstream that transfers water pressure into the valley walls."},
{"id": "pile_driver", "name": "Pile driver", "year": -55, "cat": "construction", "wiki": "Pile driver", "req": ["pulley", "lever"], "desc": "A machine that drops a heavy weight to drive piles into the ground for foundations."},
{"id": "cofferdam", "name": "Cofferdam", "year": -55, "cat": "construction", "wiki": "Cofferdam", "req": ["pile_driver"], "desc": "A temporary watertight enclosure pumped dry so that foundations can be built underwater."},
{"id": "de_architectura", "name": "De architectura", "year": -25, "cat": "construction", "wiki": "De architectura", "req": ["writing", "geometry"], "desc": "Vitruvius's treatise on building, materials and machines, the only surviving ancient architecture manual."},
{"id": "pont_du_gard", "name": "Pont du Gard", "year": 50, "cat": "construction", "wiki": "Pont du Gard", "req": ["roman_aqueduct", "arch_bridge"], "desc": "A three-tiered Roman aqueduct bridge in southern France, built of dry-laid ashlar."},
{"id": "colosseum", "name": "Colosseum", "year": 80, "cat": "construction", "wiki": "Colosseum", "req": ["groin_vault", "classical_order", "roman_concrete"], "desc": "Rome's amphitheater for some 50,000 spectators, built on vaulted concrete and stone arcades."},
{"id": "buttress_dam", "name": "Buttress dam", "year": 100, "cat": "construction", "wiki": "Buttress dam", "req": ["gravity_dam"], "desc": "A dam with a thin wall braced by buttresses on the downstream side, saving material."},
{"id": "pantheon", "name": "Pantheon, Rome", "year": 125, "cat": "construction", "wiki": "Pantheon, Rome", "req": ["dome", "roman_concrete"], "desc": "Hadrian's temple whose unreinforced concrete dome stayed the world's largest for over a millennium."},
{"id": "squinch", "name": "Squinch", "year": 250, "cat": "construction", "wiki": "Squinch", "req": ["dome"], "desc": "A small arch across the corner of a square room that lets a round dome sit on it, developed in Sasanian Persia."},
{"id": "pagoda", "name": "Pagoda", "year": 500, "cat": "construction", "wiki": "Pagoda", "req": ["dougong"], "desc": "A tiered tower, often of timber, whose flexible central post helped it survive earthquakes."},
{"id": "pendentive", "name": "Pendentive", "year": 537, "cat": "construction", "wiki": "Pendentive", "req": ["dome"], "desc": "A curved triangle of vaulting that carries a dome over a square base, as in Hagia Sophia."},
{"id": "hagia_sophia", "name": "Hagia Sophia", "year": 537, "cat": "construction", "wiki": "Hagia Sophia", "req": ["pendentive", "fired_brick"], "desc": "Justinian's church whose great dome on pendentives became a model for Byzantine and Ottoman buildings."},
{"id": "pointed_arch", "name": "Pointed arch", "year": 600, "cat": "construction", "wiki": "Pointed arch", "req": ["true_arch"], "desc": "An arch with a pointed crown that pushes less sideways, used in Islamic and later Gothic building."},
{"id": "stepwell", "name": "Stepwell", "year": 600, "cat": "construction", "wiki": "Stepwell", "req": ["cistern"], "desc": "An Indian well or reservoir reached by descending flights of steps, storing water through dry seasons."},
{"id": "anji_bridge", "name": "Anji Bridge", "year": 605, "cat": "construction", "wiki": "Anji Bridge", "req": ["arch_bridge"], "desc": "The oldest standing open-spandrel segmental stone arch bridge, built by Li Chun in China."},
{"id": "muqarnas", "name": "Muqarnas", "year": 1000, "cat": "construction", "wiki": "Muqarnas", "req": ["squinch"], "desc": "Honeycomb-like corbelled vaulting used to transition between surfaces in Islamic architecture."},
{"id": "rib_vault", "name": "Rib vault", "year": 1093, "cat": "construction", "wiki": "Rib vault", "req": ["groin_vault", "pointed_arch"], "desc": "A vault built on a framework of crossing stone ribs, lighter than solid vaults."},
{"id": "yingzao_fashi", "name": "Yingzao Fashi", "year": 1103, "cat": "construction", "wiki": "Yingzao Fashi", "req": ["dougong", "writing"], "desc": "A Song dynasty building manual that standardized modular timber construction."},
{"id": "gothic_architecture", "name": "Gothic architecture", "year": 1144, "cat": "construction", "wiki": "Gothic architecture", "req": ["rib_vault", "pointed_arch"], "desc": "A style combining rib vaults and pointed arches to build tall, light-filled churches."},
{"id": "flying_buttress", "name": "Flying buttress", "year": 1163, "cat": "construction", "wiki": "Flying buttress", "req": ["gothic_architecture"], "desc": "An external arched prop that carries vault thrust away from walls, allowing large windows."},
{"id": "chimney", "name": "Chimney", "year": 1185, "cat": "construction", "wiki": "Chimney", "req": ["fired_brick", "control_of_fire", "lime_mortar"], "desc": "A flue that draws smoke out of a building and improves the draft of a fire."},
{"id": "tracery", "name": "Tracery", "year": 1200, "cat": "construction", "wiki": "Tracery", "req": ["gothic_architecture"], "desc": "Stone ribs dividing Gothic windows to support large areas of glass."},
{"id": "fan_vault", "name": "Fan vault", "year": 1351, "cat": "construction", "wiki": "Fan vault", "req": ["rib_vault"], "desc": "An English Gothic vault of cone-shaped clusters of equal ribs."},
{"id": "hammerbeam_roof", "name": "Hammerbeam roof", "year": 1395, "cat": "construction", "wiki": "Hammerbeam roof", "req": ["timber_framing"], "desc": "A timber roof with short cantilevered beams, letting it span wide halls such as Westminster Hall."},
{"id": "florence_cathedral", "name": "Florence Cathedral", "year": 1436, "cat": "construction", "wiki": "Florence Cathedral", "req": ["dome", "gothic_architecture", "crane_machine", "fired_brick"], "desc": "Brunelleschi's double-shell brick dome, built without centering, the largest masonry dome."},
{"id": "truss", "name": "Truss", "year": 1570, "cat": "construction", "wiki": "Truss", "req": ["timber_framing", "geometry"], "desc": "A rigid framework of triangles that carries loads efficiently through members in tension and compression."},
{"id": "strength_of_materials", "name": "Strength of materials", "year": 1638, "cat": "construction", "wiki": "Strength of materials", "req": ["geometry", "scientific_method"], "desc": "The science of how materials and beams resist loads, founded in Galileo's Two New Sciences."},
{"id": "cast_iron_pipe", "name": "Cast iron pipe", "year": 1664, "cat": "construction", "wiki": "Cast iron pipe", "req": ["cast_iron"], "desc": "Pressure pipes of cast iron, first laid at Versailles, that made large water mains possible."},
{"id": "plate_glass", "name": "Plate glass", "year": 1688, "cat": "construction", "wiki": "Plate glass", "req": ["glass", "metal_casting"], "desc": "Large flat sheets of cast and polished glass for windows and mirrors."},
{"id": "beam_theory", "name": "Euler-Bernoulli beam theory", "year": 1750, "cat": "construction", "wiki": "Euler–Bernoulli beam theory", "req": ["calculus", "classical_mechanics", "strength_of_materials"], "desc": "A mathematical model of beam bending that underlies the design of girders and frames."},
{"id": "lightning_rod", "name": "Lightning rod", "year": 1752, "cat": "construction", "wiki": "Lightning rod", "req": ["scientific_method", "leyden_jar"], "desc": "Benjamin Franklin's grounded metal rod that protects buildings from lightning strikes."},
{"id": "hydraulic_lime", "name": "Hydraulic lime", "year": 1756, "cat": "construction", "wiki": "Hydraulic lime", "req": ["lime_mortar"], "desc": "Lime that sets underwater, rediscovered by John Smeaton for the Eddystone Lighthouse."},
{"id": "eddystone_lighthouse", "name": "Eddystone Lighthouse", "year": 1759, "cat": "construction", "wiki": "Eddystone Lighthouse", "req": ["lighthouse", "hydraulic_lime"], "desc": "Smeaton's dovetailed granite tower on a wave-swept reef, a founding work of civil engineering."},
{"id": "iron_bridge", "name": "The Iron Bridge", "year": 1779, "cat": "construction", "wiki": "The Iron Bridge", "req": ["cast_iron", "coke_fuel", "arch_bridge"], "desc": "The first major bridge made of cast iron, spanning the Severn at Coalbrookdale."},
{"id": "cast_iron_architecture", "name": "Cast-iron architecture", "year": 1796, "cat": "construction", "wiki": "Cast-iron architecture", "req": ["cast_iron", "coke_fuel"], "desc": "Buildings framed and faced with cast-iron columns and beams, cheap, fast and fire-resistant."},
{"id": "ditherington_flax_mill", "name": "Ditherington Flax Mill", "year": 1797, "cat": "construction", "wiki": "Shrewsbury Flaxmill Maltings", "req": ["cast_iron_architecture"], "desc": "The first iron-framed building, often called the grandfather of skyscrapers."},
{"id": "water_supply_network", "name": "Water supply network", "year": 1801, "cat": "construction", "wiki": "Water supply network", "req": ["cast_iron_pipe", "steam_engine"], "desc": "Pumped, pressurized citywide water mains delivering water to buildings, as at Philadelphia."},
{"id": "suspension_bridge", "name": "Suspension bridge", "year": 1801, "cat": "construction", "wiki": "Suspension bridge", "req": ["iron_working", "classical_mechanics"], "desc": "A deck hung from iron chains or cables slung between towers, spanning great distances."},
{"id": "slow_sand_filter", "name": "Slow sand filter", "year": 1804, "cat": "construction", "wiki": "Slow sand filter", "req": ["water_supply_network", "plumbing"], "desc": "Beds of sand that filter and biologically clean drinking water for a whole town."},
{"id": "tunnelling_shield", "name": "Tunnelling shield", "year": 1825, "cat": "construction", "wiki": "Tunnelling shield", "req": ["cast_iron", "screw"], "desc": "Brunel's movable iron frame that protects workers digging through soft ground, used for the Thames Tunnel."},
{"id": "menai_suspension_bridge", "name": "Menai Suspension Bridge", "year": 1826, "cat": "construction", "wiki": "Menai Suspension Bridge", "req": ["suspension_bridge"], "desc": "Telford's wrought-iron chain bridge, the first large suspension bridge."},
{"id": "central_heating", "name": "Central heating", "year": 1830, "cat": "construction", "wiki": "Central heating", "req": ["cast_iron_pipe", "thermodynamics", "plumbing", "steam_engine"], "desc": "A single boiler or furnace heating a whole building through pipes or ducts."},
{"id": "balloon_framing", "name": "Balloon framing", "year": 1832, "cat": "construction", "wiki": "Framing (construction)", "req": ["timber_framing", "machine_tools"], "desc": "Light frames of sawn lumber and machine-made nails, letting houses be built quickly by few workers."},
{"id": "prefabrication", "name": "Prefabrication", "year": 1833, "cat": "construction", "wiki": "Prefabrication", "req": ["timber_framing", "interchangeable_parts"], "desc": "Making building components in a factory for rapid assembly on site."},
{"id": "steam_shovel", "name": "Steam shovel", "year": 1839, "cat": "construction", "wiki": "Steam shovel", "req": ["watt_steam_engine"], "desc": "A steam-powered digging machine that moved earth for railways and canals."},
{"id": "truss_bridge", "name": "Truss bridge", "year": 1840, "cat": "construction", "wiki": "Truss bridge", "req": ["truss", "cast_iron", "railway"], "desc": "Bridges of triangulated timber or iron frames, built by the thousand for railways."},
{"id": "caisson", "name": "Caisson", "year": 1841, "cat": "construction", "wiki": "Caisson (engineering)", "req": ["cofferdam", "steam_engine"], "desc": "A pressurized watertight chamber sunk to bedrock so foundations can be dug below water."},
{"id": "thames_tunnel", "name": "Thames Tunnel", "year": 1843, "cat": "construction", "wiki": "Thames Tunnel", "req": ["tunnelling_shield", "steam_engine"], "desc": "The first tunnel built under a navigable river, dug with Brunel's shield."},
{"id": "plate_girder_bridge", "name": "Plate girder bridge", "year": 1847, "cat": "construction", "wiki": "Plate girder bridge", "req": ["beam_theory", "iron_working", "railway"], "desc": "A bridge carried by deep riveted iron or steel girders, common for short railway spans."},
{"id": "ferrocement", "name": "Ferrocement", "year": 1848, "cat": "construction", "wiki": "Ferrocement", "req": ["portland_cement"], "desc": "Thin cement mortar over iron mesh, first used by Lambot for a boat."},
{"id": "i_beam", "name": "I-beam", "year": 1849, "cat": "construction", "wiki": "I-beam", "req": ["beam_theory", "iron_working", "rolling_mill"], "desc": "A rolled beam with an I-shaped cross-section that puts material where bending stress is highest."},
{"id": "jackhammer", "name": "Pneumatic drill", "year": 1849, "cat": "construction", "wiki": "Jackhammer", "req": ["steam_engine"], "desc": "A percussive rock drill driven by steam and later compressed air, speeding tunneling and demolition."},
{"id": "box_girder_bridge", "name": "Box girder bridge", "year": 1850, "cat": "construction", "wiki": "Box girder bridge", "req": ["beam_theory", "railway"], "desc": "A bridge built from hollow box-section girders, first as the wrought-iron tubes of the Britannia Bridge."},
{"id": "britannia_bridge", "name": "Britannia Bridge", "year": 1850, "cat": "construction", "wiki": "Britannia Bridge", "req": ["box_girder_bridge", "wrought_iron", "rivet"], "desc": "Stephenson's wrought-iron tubular railway bridge over the Menai Strait."},
{"id": "water_tower", "name": "Water tower", "year": 1850, "cat": "construction", "wiki": "Water tower", "req": ["water_supply_network"], "desc": "An elevated tank that keeps water mains pressurized and stores reserve supply."},
{"id": "crystal_palace", "name": "The Crystal Palace", "year": 1851, "cat": "construction", "wiki": "The Crystal Palace", "req": ["prefabrication", "plate_glass", "cast_iron_architecture"], "desc": "Paxton's prefabricated iron and glass exhibition hall, assembled in months."},
{"id": "safety_elevator", "name": "Safety elevator", "year": 1852, "cat": "construction", "wiki": "Elevator", "req": ["pulley", "steam_engine"], "desc": "Otis's elevator with a brake that catches the car if the rope breaks, making tall buildings usable."},
{"id": "reinforced_concrete", "name": "Reinforced concrete", "year": 1853, "cat": "construction", "wiki": "Reinforced concrete", "req": ["portland_cement", "ferrocement"], "desc": "Concrete with embedded iron or steel bars to carry tension, the dominant modern structural material."},
{"id": "radiator_heating", "name": "Radiator", "year": 1857, "cat": "construction", "wiki": "Radiator (heating)", "req": ["central_heating"], "desc": "A cast-iron heat exchanger that releases heat from steam or hot water into a room."},
{"id": "fire_escape", "name": "Fire escape", "year": 1860, "cat": "construction", "wiki": "Fire escape", "req": ["cast_iron_architecture"], "desc": "External iron stairs and balconies that give occupants a way out of burning buildings."},
{"id": "ground_freezing", "name": "Ground freezing", "year": 1862, "cat": "construction", "wiki": "Ground freezing", "req": ["refrigeration"], "desc": "Freezing waterlogged soil with brine pipes so shafts and tunnels can be dug safely."},
{"id": "oriel_chambers", "name": "Oriel Chambers", "year": 1864, "cat": "construction", "wiki": "Oriel Chambers", "req": ["cast_iron_architecture", "plate_glass"], "desc": "A Liverpool office building with one of the first metal-framed glass curtain walls."},
{"id": "cantilever_bridge", "name": "Cantilever bridge", "year": 1867, "cat": "construction", "wiki": "Cantilever bridge", "req": ["truss_bridge", "beam_theory"], "desc": "A bridge built from arms projecting from piers, which can be erected without falsework."},
{"id": "fire_sprinkler", "name": "Fire sprinkler system", "year": 1874, "cat": "construction", "wiki": "Fire sprinkler system", "req": ["water_supply_network"], "desc": "Ceiling pipes with heat-triggered heads that release water directly onto a fire."},
{"id": "eads_bridge", "name": "Eads Bridge", "year": 1874, "cat": "construction", "wiki": "Eads Bridge", "req": ["arch_bridge", "caisson", "bessemer_process", "steel"], "desc": "The first major bridge built of steel, with tubular arches over the Mississippi."},
{"id": "tunnel_boring_machine", "name": "Tunnel boring machine", "year": 1880, "cat": "construction", "wiki": "Tunnel boring machine", "req": ["tunnelling_shield", "machine_tools", "pneumatic_tool"], "desc": "A machine with a rotating cutting head that excavates a full tunnel face continuously."},
{"id": "brooklyn_bridge", "name": "Brooklyn Bridge", "year": 1883, "cat": "construction", "wiki": "Brooklyn Bridge", "req": ["suspension_bridge", "caisson", "bessemer_process", "wire_rope"], "desc": "The first steel-wire suspension bridge, whose caisson foundations reached bedrock under the East River."},
{"id": "steel_frame", "name": "Steel frame", "year": 1885, "cat": "construction", "wiki": "Steel frame", "req": ["bessemer_process", "cast_iron_architecture", "i_beam"], "desc": "A skeleton of steel columns and beams that carries all loads, freeing walls from bearing weight."},
{"id": "skyscraper", "name": "Skyscraper", "year": 1885, "cat": "construction", "wiki": "Skyscraper", "req": ["steel_frame", "safety_elevator"], "desc": "A tall, continuously habitable building made possible by steel frames and elevators."},
{"id": "rapid_sand_filter", "name": "Rapid sand filter", "year": 1885, "cat": "construction", "wiki": "Rapid sand filter", "req": ["slow_sand_filter"], "desc": "A compact filter using coagulants and backwashing to treat large volumes of water quickly."},
{"id": "home_insurance_building", "name": "Home Insurance Building", "year": 1885, "cat": "construction", "wiki": "Home Insurance Building", "req": ["steel_frame"], "desc": "A Chicago office tower often called the first skyscraper for its load-bearing metal frame."},
{"id": "glass_brick", "name": "Glass brick", "year": 1886, "cat": "construction", "wiki": "Glass brick", "req": ["glass"], "desc": "Hollow pressed-glass blocks that let light through walls and floors."},
{"id": "eiffel_tower", "name": "Eiffel Tower", "year": 1889, "cat": "construction", "wiki": "Eiffel Tower", "req": ["truss", "iron_working", "prefabrication", "rivet", "wrought_iron"], "desc": "A 300 m wrought-iron lattice tower of prefabricated riveted parts, the tallest structure of its time."},
{"id": "forth_bridge", "name": "Forth Bridge", "year": 1890, "cat": "construction", "wiki": "Forth Bridge", "req": ["cantilever_bridge", "bessemer_process"], "desc": "A giant steel cantilever railway bridge in Scotland built after the Tay Bridge disaster."},
{"id": "earthquake_engineering", "name": "Earthquake engineering", "year": 1891, "cat": "construction", "wiki": "Earthquake engineering", "req": ["strength_of_materials", "steel_frame"], "desc": "The study and design of structures to survive seismic shaking, born in Meiji Japan."},
{"id": "wainwright_building", "name": "Wainwright Building", "year": 1891, "cat": "construction", "wiki": "Wainwright Building", "req": ["skyscraper"], "desc": "Louis Sullivan's St. Louis tower that defined the expressive tall office building."},
{"id": "glulam", "name": "Glued laminated timber", "year": 1893, "cat": "construction", "wiki": "Glued laminated timber", "req": ["timber_framing"], "desc": "Layers of lumber glued into large beams and arches stronger than any single log."},
{"id": "moving_walkway", "name": "Moving walkway", "year": 1893, "cat": "construction", "wiki": "Moving walkway", "req": ["electric_motor"], "desc": "A slow conveyor belt that carries pedestrians along a level or gentle incline."},
{"id": "escalator", "name": "Escalator", "year": 1896, "cat": "construction", "wiki": "Escalator", "req": ["electric_motor", "safety_elevator"], "desc": "A motorized moving staircase that carries large crowds between floors."},
{"id": "hyperboloid_structure", "name": "Hyperboloid structure", "year": 1896, "cat": "construction", "wiki": "Hyperboloid structure", "req": ["steel", "geometry"], "desc": "Shukhov's lattice towers of straight steel bars forming a doubly curved, light and stiff shell."},
{"id": "tensile_structure", "name": "Tensile structure", "year": 1896, "cat": "construction", "wiki": "Tensile structure", "req": ["steel", "cordage"], "desc": "Structures whose roofs are carried by members in tension only, such as steel cable nets and membranes."},
{"id": "gridshell", "name": "Gridshell", "year": 1896, "cat": "construction", "wiki": "Gridshell", "req": ["steel", "geometry"], "desc": "A doubly curved shell made from a lattice grid, first built by Shukhov."},
{"id": "concrete_mixer", "name": "Concrete mixer", "year": 1900, "cat": "construction", "wiki": "Concrete mixer", "req": ["portland_cement", "steam_engine"], "desc": "A rotating drum that combines cement, aggregate and water into uniform concrete."},
{"id": "concrete_masonry_unit", "name": "Concrete block", "year": 1900, "cat": "construction", "wiki": "Concrete block", "req": ["portland_cement"], "desc": "Standard hollow blocks of cast concrete, a cheap and fast walling material."},
{"id": "asphalt_shingle", "name": "Asphalt shingle", "year": 1901, "cat": "construction", "wiki": "Asphalt shingle", "req": ["oil_refining"], "desc": "Mat roofing shingles coated with asphalt and granules, the most common North American roof."},
{"id": "air_conditioning", "name": "Air conditioning", "year": 1902, "cat": "construction", "wiki": "Air conditioning", "req": ["refrigeration", "electric_motor"], "desc": "Willis Carrier's system for controlling indoor temperature and humidity with refrigeration."},
{"id": "flatiron_building", "name": "Flatiron Building", "year": 1902, "cat": "construction", "wiki": "Flatiron Building", "req": ["skyscraper"], "desc": "A triangular steel-framed New York skyscraper on a narrow wedge-shaped lot."},
{"id": "precast_concrete", "name": "Precast concrete", "year": 1905, "cat": "construction", "wiki": "Precast concrete", "req": ["reinforced_concrete"], "desc": "Concrete elements cast in a factory and lifted into place, speeding construction."},
{"id": "shotcrete", "name": "Shotcrete", "year": 1907, "cat": "construction", "wiki": "Shotcrete", "req": ["portland_cement", "pneumatic_tool"], "desc": "Concrete sprayed through a hose at high speed onto a surface, used for tunnel linings and slopes."},
{"id": "space_frame", "name": "Space frame", "year": 1907, "cat": "construction", "wiki": "Space frame", "req": ["truss", "steel"], "desc": "A three-dimensional truss of interlocking struts that spans large roofs with little material."},
{"id": "tilt_up", "name": "Tilt-up construction", "year": 1908, "cat": "construction", "wiki": "Tilt up", "req": ["reinforced_concrete"], "desc": "Casting concrete wall panels flat on site and tilting them upright with a crane."},
{"id": "water_chlorination", "name": "Water chlorination", "year": 1908, "cat": "construction", "wiki": "Water chlorination", "req": ["germ_theory", "electrolysis", "water_supply_network", "slow_sand_filter", "bleach"], "desc": "Adding chlorine to public water supplies to kill pathogens, sharply cutting typhoid and cholera."},
{"id": "kit_house", "name": "Kit house", "year": 1908, "cat": "construction", "wiki": "Kit house", "req": ["prefabrication", "balloon_framing", "railway"], "desc": "Mail-order houses shipped as precut lumber and parts for owner assembly."},
{"id": "immersed_tube", "name": "Immersed tube tunnel", "year": 1910, "cat": "construction", "wiki": "Immersed tube", "req": ["reinforced_concrete", "caisson"], "desc": "Prefabricated tunnel sections floated into place and sunk into a trench on the seabed or riverbed."},
{"id": "slip_forming", "name": "Slip forming", "year": 1910, "cat": "construction", "wiki": "Slip forming", "req": ["reinforced_concrete", "formwork"], "desc": "Pouring concrete continuously into a form that climbs steadily, used for silos, towers and cores."},
{"id": "ready_mix_concrete", "name": "Ready-mix concrete", "year": 1913, "cat": "construction", "wiki": "Ready-mix concrete", "req": ["concrete_mixer", "automobile"], "desc": "Concrete batched at a plant and delivered in mixer trucks to the site."},
{"id": "drywall", "name": "Drywall", "year": 1916, "cat": "construction", "wiki": "Drywall", "req": ["paper", "kiln"], "desc": "Gypsum board faced with paper that replaced wet plaster for interior walls."},
{"id": "curtain_wall", "name": "Curtain wall", "year": 1918, "cat": "construction", "wiki": "Curtain wall (architecture)", "req": ["steel_frame", "plate_glass"], "desc": "A non-structural outer skin, usually glass, hung on a building's frame."},
{"id": "bulldozer", "name": "Bulldozer", "year": 1923, "cat": "construction", "wiki": "Bulldozer", "req": ["internal_combustion_engine", "continuous_track"], "desc": "A tracked tractor with a front blade for pushing earth and clearing sites."},
{"id": "soil_mechanics", "name": "Soil mechanics", "year": 1925, "cat": "construction", "wiki": "Soil mechanics", "req": ["classical_mechanics", "strength_of_materials"], "desc": "Terzaghi's science of soil behavior under load, the basis of foundation engineering."},
{"id": "thin_shell_structure", "name": "Thin-shell structure", "year": 1925, "cat": "construction", "wiki": "Shell (structure)", "req": ["reinforced_concrete"], "desc": "Curved reinforced concrete shells only centimeters thick that span wide roofs."},
{"id": "geodesic_dome", "name": "Geodesic dome", "year": 1926, "cat": "construction", "wiki": "Geodesic dome", "req": ["steel", "geometry"], "desc": "A dome of triangulated struts on a sphere, first built for the Jena planetarium and popularized by Fuller."},
{"id": "concrete_pump", "name": "Concrete pump", "year": 1927, "cat": "construction", "wiki": "Concrete pump", "req": ["ready_mix_concrete", "internal_combustion_engine"], "desc": "A machine that pumps liquid concrete through pipes to where it is poured."},
{"id": "prestressed_concrete", "name": "Prestressed concrete", "year": 1928, "cat": "construction", "wiki": "Prestressed concrete", "req": ["reinforced_concrete", "steel"], "desc": "Freyssinet's concrete precompressed by tensioned steel tendons, allowing long slender spans."},
{"id": "hvac", "name": "HVAC", "year": 1928, "cat": "construction", "wiki": "Heating, ventilation, and air conditioning", "req": ["air_conditioning", "central_heating"], "desc": "Integrated building systems for heating, ventilation and cooling, standard in large buildings."},
{"id": "empire_state_building", "name": "Empire State Building", "year": 1931, "cat": "construction", "wiki": "Empire State Building", "req": ["skyscraper"], "desc": "A 102-storey steel-framed tower built in about a year, the world's tallest for four decades."},
{"id": "building_insulation", "name": "Building insulation", "year": 1933, "cat": "construction", "wiki": "Building insulation", "req": ["glass", "glass_fiber"], "desc": "Glass wool and other materials in walls and roofs that cut heat loss and gain."},
{"id": "insulated_glazing", "name": "Insulated glazing", "year": 1934, "cat": "construction", "wiki": "Insulated glazing", "req": ["plate_glass"], "desc": "Double or triple panes sealed around a gas gap to reduce heat transfer through windows."},
{"id": "hoover_dam", "name": "Hoover Dam", "year": 1936, "cat": "construction", "wiki": "Hoover Dam", "req": ["arch_dam", "portland_cement", "francis_turbine", "polyphase_system", "hydroelectricity"], "desc": "A concrete arch-gravity dam on the Colorado River, cooled with embedded pipes as it set."},
{"id": "golden_gate_bridge", "name": "Golden Gate Bridge", "year": 1937, "cat": "construction", "wiki": "Golden Gate Bridge", "req": ["suspension_bridge", "wire_rope", "steel"], "desc": "A 1,280 m steel suspension span, the longest in the world when it opened."},
{"id": "bailey_bridge", "name": "Bailey bridge", "year": 1941, "cat": "construction", "wiki": "Bailey bridge", "req": ["truss_bridge", "prefabrication", "steel"], "desc": "A portable prefabricated steel truss bridge assembled by hand without heavy equipment."},
{"id": "air_supported_structure", "name": "Air-supported structure", "year": 1946, "cat": "construction", "wiki": "Air-supported structure", "req": ["tensile_structure", "electric_motor"], "desc": "A fabric membrane held up by slight internal air pressure from fans, covering large spaces."},
{"id": "tensegrity", "name": "Tensegrity", "year": 1948, "cat": "construction", "wiki": "Tensegrity", "req": ["tensile_structure", "geometry"], "desc": "Structures of isolated compression struts held in a continuous net of tension cables."},
{"id": "slurry_wall", "name": "Slurry wall", "year": 1950, "cat": "construction", "wiki": "Slurry wall", "req": ["reinforced_concrete", "soil_mechanics"], "desc": "A concrete wall cast in a trench held open by bentonite slurry, used for deep basements."},
{"id": "large_panel_building", "name": "Large-panel-system building", "year": 1950, "cat": "construction", "wiki": "Large-panel-system building", "req": ["precast_concrete", "prefabrication"], "desc": "Mass housing assembled from storey-height precast concrete panels, widespread in the Soviet bloc."},
{"id": "excavator", "name": "Hydraulic excavator", "year": 1951, "cat": "construction", "wiki": "Excavator", "req": ["steam_shovel", "internal_combustion_engine"], "desc": "A digging machine with a hydraulic boom and bucket on a rotating cab."},
{"id": "cable_stayed_bridge", "name": "Cable-stayed bridge", "year": 1955, "cat": "construction", "wiki": "Cable-stayed bridge", "req": ["suspension_bridge", "steel", "wire_rope"], "desc": "A bridge deck held directly by straight cables running down from towers."},
{"id": "storm_surge_barrier", "name": "Storm surge barrier", "year": 1958, "cat": "construction", "wiki": "Flood barrier", "req": ["levee", "steel"], "desc": "Movable gates across an estuary that close against storm tides."},
{"id": "geotextile", "name": "Geotextile", "year": 1958, "cat": "construction", "wiki": "Geotextile", "req": ["bakelite", "soil_mechanics", "pvc"], "desc": "Permeable synthetic fabrics laid in soil to separate, filter, drain and reinforce it."},
{"id": "modular_building", "name": "Modular building", "year": 1960, "cat": "construction", "wiki": "Modular building", "req": ["prefabrication", "precast_concrete"], "desc": "Buildings assembled from whole factory-made volumetric modules."},
{"id": "retractable_roof", "name": "Retractable roof", "year": 1961, "cat": "construction", "wiki": "Retractable roof", "req": ["steel", "electric_motor"], "desc": "A stadium or arena roof that opens and closes on motorized tracks."},
{"id": "natm", "name": "New Austrian tunnelling method", "year": 1962, "cat": "construction", "wiki": "New Austrian tunneling method", "req": ["shotcrete", "soil_mechanics"], "desc": "Tunneling that uses the surrounding rock as support, lined quickly with shotcrete and bolts."},
{"id": "mechanically_stabilized_earth", "name": "Mechanically stabilized earth", "year": 1963, "cat": "construction", "wiki": "Mechanically stabilized earth", "req": ["steel", "soil_mechanics"], "desc": "Henri Vidal's soil reinforced with layered strips, forming retaining walls and embankments."},
{"id": "tube_structure", "name": "Tube structure", "year": 1963, "cat": "construction", "wiki": "Tube (structure)", "req": ["skyscraper", "reinforced_concrete"], "desc": "Fazlur Khan's system where the outer frame acts as a hollow tube, enabling very tall towers economically."},
{"id": "fiber_reinforced_concrete", "name": "Fiber-reinforced concrete", "year": 1963, "cat": "construction", "wiki": "Fiber-reinforced concrete", "req": ["portland_cement", "steel"], "desc": "Concrete with dispersed steel, glass or synthetic fibers that improve crack resistance."},
{"id": "reverse_osmosis", "name": "Reverse osmosis", "year": 1965, "cat": "construction", "wiki": "Reverse osmosis", "req": ["modern_chemistry", "electric_motor", "cellulose_acetate"], "desc": "Pushing water through a semi-permeable membrane to remove salts, used for desalination and purification."},
{"id": "habitat_67", "name": "Habitat 67", "year": 1967, "cat": "construction", "wiki": "Habitat 67", "req": ["modular_building"], "desc": "Moshe Safdie's Montreal housing complex of stacked precast concrete modules."},
{"id": "base_isolation", "name": "Seismic base isolation", "year": 1969, "cat": "construction", "wiki": "Seismic base isolation", "req": ["earthquake_engineering", "vulcanization"], "desc": "Flexible bearings under a building that decouple it from ground shaking during earthquakes."},
{"id": "olympiastadion_munich", "name": "Olympiastadion Munich", "year": 1972, "cat": "construction", "wiki": "Olympiastadion (Munich)", "req": ["tensile_structure", "pmma", "wire_rope"], "desc": "Frei Otto's stadium roofed with a sweeping cable-net and acrylic tensile canopy."},
{"id": "sydney_opera_house", "name": "Sydney Opera House", "year": 1973, "cat": "construction", "wiki": "Sydney Opera House", "req": ["precast_concrete", "thin_shell_structure", "electronic_computer"], "desc": "Utzon's shells built from precast concrete ribs, an early computer-analysed structure."},
{"id": "cn_tower", "name": "CN Tower", "year": 1976, "cat": "construction", "wiki": "CN Tower", "req": ["slip_forming"], "desc": "A 553 m slipformed concrete tower in Toronto, the world's tallest free-standing structure for decades."},
{"id": "tuned_mass_damper", "name": "Tuned mass damper", "year": 1977, "cat": "construction", "wiki": "Tuned mass damper", "req": ["skyscraper", "classical_mechanics"], "desc": "A large tuned weight that counteracts the sway of tall buildings in wind and earthquakes."},
{"id": "building_automation", "name": "Building automation", "year": 1980, "cat": "construction", "wiki": "Building automation", "req": ["microprocessor", "hvac"], "desc": "Computerized control of a building's heating, cooling, lighting and security."},
{"id": "extradosed_bridge", "name": "Extradosed bridge", "year": 1980, "cat": "construction", "wiki": "Extradosed bridge", "req": ["cable_stayed_bridge", "prestressed_concrete"], "desc": "A hybrid of girder and cable-stayed bridge with low towers and shallow stay cables."},
{"id": "roller_compacted_concrete", "name": "Roller-compacted concrete", "year": 1982, "cat": "construction", "wiki": "Roller-compacted concrete", "req": ["gravity_dam", "portland_cement", "bulldozer"], "desc": "Dry concrete spread and compacted with earthmoving rollers, making dams fast and cheap."},
{"id": "self_consolidating_concrete", "name": "Self-consolidating concrete", "year": 1986, "cat": "construction", "wiki": "Self-consolidating concrete", "req": ["reinforced_concrete"], "desc": "Highly fluid concrete that flows around dense reinforcement without vibration."},
{"id": "bim", "name": "Building information modeling", "year": 1987, "cat": "construction", "wiki": "Building information modeling", "req": ["personal_computer", "computer_aided_design"], "desc": "Shared 3D digital models holding a building's geometry and data through design, construction and operation."},
{"id": "passive_house", "name": "Passive house", "year": 1990, "cat": "construction", "wiki": "Passive house", "req": ["building_insulation", "insulated_glazing", "hvac"], "desc": "A standard for airtight, superinsulated buildings with heat-recovery ventilation that need little heating."},
{"id": "green_building", "name": "Green building", "year": 1990, "cat": "construction", "wiki": "Green building", "req": ["building_insulation", "solar_cell"], "desc": "Design and rating systems such as BREEAM and LEED that reduce a building's environmental impact."},
{"id": "building_integrated_photovoltaics", "name": "Building-integrated photovoltaics", "year": 1991, "cat": "construction", "wiki": "Building-integrated photovoltaics", "req": ["solar_cell", "curtain_wall"], "desc": "Solar cells built into roofs, facades and glazing as part of the building envelope."},
{"id": "channel_tunnel", "name": "Channel Tunnel", "year": 1994, "cat": "construction", "wiki": "Channel Tunnel", "req": ["tunnel_boring_machine"], "desc": "A 50 km rail tunnel under the English Channel bored by eleven TBMs."},
{"id": "cross_laminated_timber", "name": "Cross-laminated timber", "year": 1995, "cat": "construction", "wiki": "Cross-laminated timber", "req": ["glulam"], "desc": "Large panels of lumber layers glued at right angles, the core material of mass timber buildings."},
{"id": "delta_works", "name": "Delta Works", "year": 1997, "cat": "construction", "wiki": "Delta Works", "req": ["storm_surge_barrier"], "desc": "The Dutch system of dams, sluices and surge barriers protecting the southwestern delta from the sea."},
{"id": "akashi_kaikyo_bridge", "name": "Akashi Kaikyo Bridge", "year": 1998, "cat": "construction", "wiki": "Akashi Kaikyo Bridge", "req": ["suspension_bridge", "tuned_mass_damper", "wire_rope", "wind_tunnel"], "desc": "A Japanese suspension bridge with a 1,991 m central span, longest in the world for over two decades."},
{"id": "millau_viaduct", "name": "Millau Viaduct", "year": 2004, "cat": "construction", "wiki": "Millau Viaduct", "req": ["cable_stayed_bridge"], "desc": "A multi-span cable-stayed bridge in France with the tallest bridge piers in the world."},
{"id": "self_healing_concrete", "name": "Self-healing concrete", "year": 2010, "cat": "construction", "wiki": "Self-healing concrete", "req": ["reinforced_concrete"], "desc": "Concrete containing bacteria or capsules that seal cracks automatically."},
{"id": "burj_khalifa", "name": "Burj Khalifa", "year": 2010, "cat": "construction", "wiki": "Burj Khalifa", "req": ["tube_structure", "concrete_pump"], "desc": "The world's tallest building at 828 m, built on a buttressed concrete core."},
{"id": "construction_3d_printing", "name": "Construction 3D printing", "year": 2014, "cat": "construction", "wiki": "Construction 3D printing", "req": ["microprocessor", "portland_cement", "3d_printing"], "desc": "Robotic extrusion of concrete layer by layer to build walls and whole houses."},
{"id": "gotthard_base_tunnel", "name": "Gotthard Base Tunnel", "year": 2016, "cat": "construction", "wiki": "Gotthard Base Tunnel", "req": ["tunnel_boring_machine"], "desc": "A 57 km railway tunnel under the Alps, the world's longest."},
{"id": "plyscraper", "name": "Plyscraper", "year": 2019, "cat": "construction", "wiki": "Plyscraper", "req": ["cross_laminated_timber", "skyscraper"], "desc": "A high-rise built mainly of mass timber, such as Norway's 85 m Mjostarnet."},
{"id": "electroscope", "name": "Electroscope", "year": 1600, "cat": "electronics", "wiki": "Electroscope", "req": ["compass"], "desc": "A device that detects electric charge, starting with Gilbert's pivoted-needle versorium; later gold-leaf versions measured it."},
{"id": "electrostatic_generator", "name": "Electrostatic generator", "year": 1663, "cat": "electronics", "wiki": "Electrostatic generator", "req": ["electroscope", "scientific_method"], "desc": "A friction machine that builds up static charge, first Guericke's sulfur globe; it made electricity available for experiment."},
{"id": "leyden_jar", "name": "Leyden jar", "year": 1745, "cat": "electronics", "wiki": "Leyden jar", "req": ["electrostatic_generator", "glass"], "desc": "A glass jar lined with metal foil that stores static charge; the first capacitor."},
{"id": "coulombs_law", "name": "Coulomb's law", "year": 1785, "cat": "electronics", "wiki": "Coulomb's law", "req": ["electroscope", "classical_mechanics"], "desc": "The inverse-square law of force between electric charges, measured with a torsion balance."},
{"id": "arc_lamp", "name": "Arc lamp", "year": 1809, "cat": "electronics", "wiki": "Arc lamp", "req": ["voltaic_pile"], "desc": "Light from an electric arc between carbon rods, the first electric light, used for streets and lighthouses."},
{"id": "galvanometer", "name": "Galvanometer", "year": 1820, "cat": "electronics", "wiki": "Galvanometer", "req": ["electromagnetism", "compass"], "desc": "A needle deflected by a current-carrying coil, the first instrument to detect and measure electric current."},
{"id": "thermocouple", "name": "Thermocouple", "year": 1821, "cat": "electronics", "wiki": "Thermocouple", "req": ["galvanometer", "voltaic_pile", "electromagnetism"], "desc": "Two dissimilar metals joined to produce a temperature-dependent voltage (Seebeck effect); a basic temperature sensor."},
{"id": "ohms_law", "name": "Ohm's law", "year": 1827, "cat": "electronics", "wiki": "Ohm's law", "req": ["voltaic_pile", "galvanometer"], "desc": "The proportional relation between voltage, current and resistance that underlies circuit design."},
{"id": "faradays_law", "name": "Faraday's law of induction", "year": 1831, "cat": "electronics", "wiki": "Faraday's law of induction", "req": ["electromagnetism"], "desc": "A changing magnetic flux induces a voltage in a conductor; the basis of generators, transformers and inductors."},
{"id": "inductor", "name": "Inductor", "year": 1832, "cat": "electronics", "wiki": "Inductor", "req": ["faradays_law", "electromagnet"], "desc": "A coil that stores energy in its magnetic field and resists changes in current; a basic passive component."},
{"id": "commutator", "name": "Commutator", "year": 1832, "cat": "electronics", "wiki": "Commutator (electric)", "req": ["electric_motor", "electric_generator"], "desc": "A rotary switch that reverses current in a machine's windings, enabling DC motors and generators."},
{"id": "relay", "name": "Relay", "year": 1835, "cat": "electronics", "wiki": "Relay", "req": ["electromagnet"], "desc": "An electromagnetically operated switch that lets a small current control a larger one; key to telegraphy and switching."},
{"id": "induction_coil", "name": "Induction coil", "year": 1836, "cat": "electronics", "wiki": "Induction coil", "req": ["inductor", "faradays_law"], "desc": "A transformer with an interrupter that turns low-voltage DC into high-voltage pulses for sparks and discharge tubes."},
{"id": "resistor", "name": "Resistor", "year": 1840, "cat": "electronics", "wiki": "Resistor", "req": ["ohms_law"], "desc": "A component that sets a fixed opposition to current, used to control voltages and currents in circuits."},
{"id": "potentiometer", "name": "Potentiometer", "year": 1841, "cat": "electronics", "wiki": "Potentiometer", "req": ["resistor"], "desc": "A resistor with a sliding contact, used to measure voltage and as an adjustable divider or control knob."},
{"id": "wheatstone_bridge", "name": "Wheatstone bridge", "year": 1843, "cat": "electronics", "wiki": "Wheatstone bridge", "req": ["galvanometer", "resistor"], "desc": "A balanced four-arm circuit that measures an unknown resistance precisely."},
{"id": "kirchhoffs_laws", "name": "Kirchhoff's circuit laws", "year": 1845, "cat": "electronics", "wiki": "Kirchhoff's circuit laws", "req": ["ohms_law"], "desc": "Conservation rules for current at nodes and voltage around loops, the foundation of circuit analysis."},
{"id": "lc_circuit", "name": "LC circuit", "year": 1857, "cat": "electronics", "wiki": "LC circuit", "req": ["leyden_jar", "inductor"], "desc": "A capacitor and inductor that oscillate at a resonant frequency; the tuning element of radio."},
{"id": "geissler_tube", "name": "Geissler tube", "year": 1857, "cat": "electronics", "wiki": "Geissler tube", "req": ["vacuum_pump", "induction_coil"], "desc": "A sealed low-pressure gas tube that glows when high voltage is applied; ancestor of neon and fluorescent lamps."},
{"id": "dynamo", "name": "Self-excited dynamo", "year": 1866, "cat": "electronics", "wiki": "Dynamo", "req": ["electric_generator", "commutator"], "desc": "A DC generator whose own output energizes its field magnets, making large-scale electric power practical."},
{"id": "crookes_tube", "name": "Crookes tube", "year": 1869, "cat": "electronics", "wiki": "Crookes tube", "req": ["geissler_tube", "vacuum_pump"], "desc": "A high-vacuum discharge tube in which cathode rays were studied, leading to X-rays and the electron."},
{"id": "gramme_machine", "name": "Gramme machine", "year": 1871, "cat": "electronics", "wiki": "Gramme machine", "req": ["dynamo"], "desc": "A ring-armature dynamo giving smooth, high DC output; the first commercially successful generator."},
{"id": "photoconductivity", "name": "Photoconductivity", "year": 1873, "cat": "electronics", "wiki": "Photoconductivity", "req": ["ohms_law"], "desc": "Discovery that selenium's resistance drops in light, the first light-sensitive electronic effect."},
{"id": "capacitor", "name": "Capacitor", "year": 1876, "cat": "electronics", "wiki": "Capacitor", "req": ["leyden_jar"], "desc": "Compact paper-and-foil and later film capacitors that store charge and filter signals in circuits."},
{"id": "hall_effect", "name": "Hall effect", "year": 1879, "cat": "electronics", "wiki": "Hall effect", "req": ["electromagnetism", "ohms_law"], "desc": "A voltage across a current-carrying conductor in a magnetic field; later used to sense fields and probe semiconductors."},
{"id": "piezoelectricity", "name": "Piezoelectricity", "year": 1880, "cat": "electronics", "wiki": "Piezoelectricity", "req": ["electroscope", "electromagnetism"], "desc": "The Curie brothers' discovery that some crystals produce voltage under stress and deform under voltage."},
{"id": "thermionic_emission", "name": "Thermionic emission", "year": 1883, "cat": "electronics", "wiki": "Thermionic emission", "req": ["light_bulb"], "desc": "Electrons boiling off a heated filament (the Edison effect), the principle behind vacuum tubes."},
{"id": "ammeter", "name": "Ammeter", "year": 1884, "cat": "electronics", "wiki": "Ammeter", "req": ["galvanometer"], "desc": "A calibrated instrument for measuring current; the moving-coil design made it rugged and accurate."},
{"id": "alternator", "name": "Alternator", "year": 1886, "cat": "electronics", "wiki": "Alternator", "req": ["electric_generator", "alternating_current"], "desc": "A generator that produces alternating current directly, used in AC power systems."},
{"id": "alternating_current", "name": "Alternating current", "year": 1886, "cat": "electronics", "wiki": "Alternating current", "req": ["transformer", "dynamo"], "desc": "Current that reverses direction periodically, easily stepped up or down by transformers for long-distance power."},
{"id": "photoelectric_effect", "name": "Photoelectric effect", "year": 1887, "cat": "electronics", "wiki": "Photoelectric effect", "req": ["induction_coil", "electromagnetic_waves"], "desc": "Emission of electrons from metals struck by light, observed by Hertz and later explained by Einstein."},
{"id": "polyphase_system", "name": "Polyphase system", "year": 1888, "cat": "electronics", "wiki": "Polyphase system", "req": ["alternating_current", "electric_motor"], "desc": "Multiple AC currents offset in phase, which produce rotating magnetic fields and efficient power transmission."},
{"id": "induction_motor", "name": "Induction motor", "year": 1888, "cat": "electronics", "wiki": "Induction motor", "req": ["polyphase_system", "faradays_law"], "desc": "A brushless AC motor driven by a rotating magnetic field; the workhorse of industry."},
{"id": "synchronous_motor", "name": "Synchronous motor", "year": 1888, "cat": "electronics", "wiki": "Synchronous motor", "req": ["alternating_current", "electric_motor"], "desc": "An AC motor that turns in exact step with the supply frequency, used for clocks and large drives."},
{"id": "liquid_crystal", "name": "Liquid crystal", "year": 1888, "cat": "electronics", "wiki": "Liquid crystal", "req": ["microscope", "modern_chemistry"], "desc": "A state of matter between liquid and solid whose molecular alignment can be switched; the basis of LCDs."},
{"id": "voltmeter", "name": "Voltmeter", "year": 1890, "cat": "electronics", "wiki": "Voltmeter", "req": ["galvanometer", "resistor"], "desc": "An instrument that measures electric potential difference, built from a galvanometer and series resistor."},
{"id": "tesla_coil", "name": "Tesla coil", "year": 1891, "cat": "electronics", "wiki": "Tesla coil", "req": ["induction_coil", "transformer", "lc_circuit"], "desc": "A resonant air-core transformer producing very high-voltage, high-frequency alternating current."},
{"id": "wireless_power", "name": "Wireless power transfer", "year": 1891, "cat": "electronics", "wiki": "Wireless power transfer", "req": ["tesla_coil"], "desc": "Transmitting electrical energy without wires, from Tesla's demonstrations to modern inductive phone chargers."},
{"id": "chemical_vapor_deposition", "name": "Chemical vapor deposition", "year": 1893, "cat": "electronics", "wiki": "Chemical vapor deposition", "req": ["light_bulb"], "desc": "Depositing thin solid films from reacting gases; first used for lamp filaments, later central to chipmaking."},
{"id": "phototube", "name": "Phototube", "year": 1893, "cat": "electronics", "wiki": "Phototube", "req": ["photoelectric_effect", "vacuum_pump"], "desc": "An evacuated tube with a light-sensitive cathode that converts light into current."},
{"id": "electrolytic_capacitor", "name": "Electrolytic capacitor", "year": 1896, "cat": "electronics", "wiki": "Electrolytic capacitor", "req": ["capacitor", "electrolysis"], "desc": "A capacitor using a thin anodized oxide film as dielectric, giving large capacitance in a small volume."},
{"id": "mercury_vapor_lamp", "name": "Mercury-vapor lamp", "year": 1901, "cat": "electronics", "wiki": "Mercury-vapor lamp", "req": ["geissler_tube"], "desc": "A gas-discharge lamp exciting mercury vapor, efficient for streets and the precursor of fluorescent tubes."},
{"id": "heterodyne", "name": "Heterodyne", "year": 1901, "cat": "electronics", "wiki": "Heterodyne", "req": ["radio"], "desc": "Mixing two frequencies to produce new sum and difference frequencies, proposed by Fessenden."},
{"id": "mercury_arc_valve", "name": "Mercury-arc valve", "year": 1902, "cat": "electronics", "wiki": "Mercury-arc valve", "req": ["mercury_vapor_lamp", "alternating_current", "vacuum_pump"], "desc": "A mercury-pool rectifier that converted high-power AC to DC for railways and industry."},
{"id": "triode", "name": "Triode", "year": 1906, "cat": "electronics", "wiki": "Triode", "req": ["vacuum_tube"], "desc": "De Forest's Audion added a control grid to the vacuum diode, making the first electronic amplifier."},
{"id": "electroluminescence", "name": "Electroluminescence", "year": 1907, "cat": "electronics", "wiki": "Electroluminescence", "req": ["crystal_detector"], "desc": "Light emitted by a material when current passes through it, first seen by Round in silicon carbide."},
{"id": "neon_lighting", "name": "Neon lighting", "year": 1910, "cat": "electronics", "wiki": "Neon lighting", "req": ["geissler_tube", "air_separation"], "desc": "Glass tubes filled with neon or other gases that glow brightly, used for signs."},
{"id": "seven_segment_display", "name": "Seven-segment display", "year": 1910, "cat": "electronics", "wiki": "Segment display", "req": ["light_bulb"], "desc": "Seven bars arranged to form any digit, the standard layout for numeric readouts."},
{"id": "amplifier", "name": "Electronic amplifier", "year": 1912, "cat": "electronics", "wiki": "Amplifier", "req": ["triode"], "desc": "A circuit that boosts a signal's power, first with triodes; it made long-distance telephony and radio practical."},
{"id": "electronic_oscillator", "name": "Electronic oscillator", "year": 1912, "cat": "electronics", "wiki": "Electronic oscillator", "req": ["regenerative_circuit", "lc_circuit"], "desc": "A circuit that generates a steady periodic signal, the source of carrier waves and clocks."},
{"id": "czochralski_method", "name": "Czochralski method", "year": 1916, "cat": "electronics", "wiki": "Czochralski method", "req": ["modern_chemistry", "crucible", "metallography"], "desc": "Pulling a single crystal from a melt; adapted in 1950 to grow the silicon and germanium for transistors."},
{"id": "neon_lamp", "name": "Neon lamp", "year": 1917, "cat": "electronics", "wiki": "Neon lamp", "req": ["neon_lighting"], "desc": "A small glow lamp with two electrodes in neon, used as indicators and voltage references."},
{"id": "flip_flop", "name": "Flip-flop", "year": 1918, "cat": "electronics", "wiki": "Flip-flop (electronics)", "req": ["triode"], "desc": "Eccles and Jordan's two-state trigger circuit that stores one bit; the basis of digital memory and counters."},
{"id": "multivibrator", "name": "Multivibrator", "year": 1919, "cat": "electronics", "wiki": "Multivibrator", "req": ["triode"], "desc": "A two-stage switching circuit that oscillates, triggers or holds state; a basic timing building block."},
{"id": "tetrode", "name": "Tetrode", "year": 1919, "cat": "electronics", "wiki": "Tetrode", "req": ["triode"], "desc": "A vacuum tube with a screen grid that cuts grid-anode capacitance, allowing higher frequency gain."},
{"id": "stepper_motor", "name": "Stepper motor", "year": 1919, "cat": "electronics", "wiki": "Stepper motor", "req": ["electric_motor", "electromagnet"], "desc": "A motor that moves in precise discrete steps, used for positioning in printers and machines."},
{"id": "crystal_oscillator", "name": "Crystal oscillator", "year": 1921, "cat": "electronics", "wiki": "Crystal oscillator", "req": ["piezoelectricity", "electronic_oscillator"], "desc": "An oscillator stabilized by a vibrating quartz crystal, the precise timebase in clocks, radios and computers."},
{"id": "power_inverter", "name": "Power inverter", "year": 1925, "cat": "electronics", "wiki": "Power inverter", "req": ["mercury_arc_valve", "alternating_current"], "desc": "A device that converts DC into AC, now built with transistors for solar systems and motor drives."},
{"id": "field_effect_transistor", "name": "Field-effect transistor concept", "year": 1925, "cat": "electronics", "wiki": "Field-effect transistor", "req": ["crystal_detector", "vacuum_tube"], "desc": "Lilienfeld's idea of controlling a semiconductor's conductivity with an electric field, realized decades later."},
{"id": "pentode", "name": "Pentode", "year": 1926, "cat": "electronics", "wiki": "Pentode", "req": ["tetrode"], "desc": "A tube with a suppressor grid that removes the tetrode's secondary-emission kink, the standard amplifier tube."},
{"id": "ceramic_capacitor", "name": "Ceramic capacitor", "year": 1926, "cat": "electronics", "wiki": "Ceramic capacitor", "req": ["capacitor"], "desc": "A small, cheap capacitor with a ceramic dielectric; multilayer versions are the most common component made."},
{"id": "negative_feedback_amplifier", "name": "Negative-feedback amplifier", "year": 1927, "cat": "electronics", "wiki": "Negative-feedback amplifier", "req": ["amplifier"], "desc": "Black's amplifier that feeds back part of its output to cut distortion and stabilize gain."},
{"id": "thyratron", "name": "Thyratron", "year": 1928, "cat": "electronics", "wiki": "Thyratron", "req": ["triode", "mercury_arc_valve"], "desc": "A gas-filled tube used as a high-power controlled switch, a precursor of the thyristor."},
{"id": "van_de_graaff", "name": "Van de Graaff generator", "year": 1929, "cat": "electronics", "wiki": "Van de Graaff generator", "req": ["electrostatic_generator", "electric_motor", "electroscope"], "desc": "A belt-charged electrostatic machine reaching millions of volts, used in early particle accelerators."},
{"id": "ferrite", "name": "Ferrite core", "year": 1930, "cat": "electronics", "wiki": "Ferrite (magnet)", "req": ["electromagnet", "modern_chemistry", "powder_metallurgy"], "desc": "Ceramic magnetic oxides with low losses at high frequency, used in inductors, transformers and antennas."},
{"id": "thermistor", "name": "Thermistor", "year": 1930, "cat": "electronics", "wiki": "Thermistor", "req": ["resistor", "modern_chemistry"], "desc": "A semiconductor resistor whose resistance changes strongly with temperature, used for sensing and protection."},
{"id": "photoresistor", "name": "Photoresistor", "year": 1930, "cat": "electronics", "wiki": "Photoresistor", "req": ["photoconductivity", "resistor"], "desc": "A cadmium sulfide or similar cell whose resistance falls with light, used in light meters and switches."},
{"id": "oscilloscope", "name": "Oscilloscope", "year": 1931, "cat": "electronics", "wiki": "Oscilloscope", "req": ["cathode_ray_tube", "amplifier"], "desc": "An instrument that draws voltage against time on a screen, the essential tool for seeing electronic signals."},
{"id": "sodium_vapor_lamp", "name": "Sodium-vapor lamp", "year": 1932, "cat": "electronics", "wiki": "Sodium-vapor lamp", "req": ["mercury_vapor_lamp"], "desc": "A very efficient discharge lamp with a yellow glow, widely used in street lighting."},
{"id": "phase_locked_loop", "name": "Phase-locked loop", "year": 1932, "cat": "electronics", "wiki": "Phase-locked loop", "req": ["electronic_oscillator", "negative_feedback_amplifier"], "desc": "A feedback system that locks an oscillator to a reference phase, used in tuning, clocks and demodulation."},
{"id": "selenium_rectifier", "name": "Selenium rectifier", "year": 1933, "cat": "electronics", "wiki": "Selenium rectifier", "req": ["semiconductor", "photoconductivity"], "desc": "A metal-semiconductor rectifier stack that was a common solid-state power rectifier before silicon diodes."},
{"id": "differential_amplifier", "name": "Differential amplifier", "year": 1934, "cat": "electronics", "wiki": "Differential amplifier", "req": ["amplifier"], "desc": "An amplifier of the difference between two inputs that rejects common noise; the core of op-amps."},
{"id": "schmitt_trigger", "name": "Schmitt trigger", "year": 1934, "cat": "electronics", "wiki": "Schmitt trigger", "req": ["triode", "multivibrator"], "desc": "A comparator with hysteresis that turns noisy signals into clean digital transitions."},
{"id": "photomultiplier", "name": "Photomultiplier tube", "year": 1934, "cat": "electronics", "wiki": "Photomultiplier tube", "req": ["phototube", "vacuum_tube", "quantum_mechanics"], "desc": "A phototube with a chain of electron-multiplying dynodes that can detect single photons."},
{"id": "waveguide", "name": "Waveguide", "year": 1936, "cat": "electronics", "wiki": "Waveguide (radio frequency)", "req": ["maxwell_equations", "radio"], "desc": "A hollow metal pipe that guides microwaves with low loss, essential for radar and microwave links."},
{"id": "printed_circuit_board", "name": "Printed circuit board", "year": 1936, "cat": "electronics", "wiki": "Printed circuit board", "req": ["bakelite", "vacuum_tube"], "desc": "Eisler's etched copper wiring on an insulating board, which made electronics compact and mass-producible."},
{"id": "klystron", "name": "Klystron", "year": 1937, "cat": "electronics", "wiki": "Klystron", "req": ["vacuum_tube", "waveguide"], "desc": "A velocity-modulated tube that amplifies microwaves, used in radar, broadcasting and particle accelerators."},
{"id": "fluorescent_lamp", "name": "Fluorescent lamp", "year": 1938, "cat": "electronics", "wiki": "Fluorescent lamp", "req": ["mercury_vapor_lamp"], "desc": "A mercury discharge tube coated with phosphor that converts ultraviolet into visible light efficiently."},
{"id": "schottky_diode", "name": "Schottky diode", "year": 1938, "cat": "electronics", "wiki": "Schottky diode", "req": ["crystal_detector", "semiconductor"], "desc": "A metal-semiconductor junction diode with low forward drop and fast switching."},
{"id": "strain_gauge", "name": "Strain gauge", "year": 1938, "cat": "electronics", "wiki": "Strain gauge", "req": ["wheatstone_bridge", "resistor"], "desc": "A resistive foil or wire whose resistance changes with stretch, used to measure force and weight."},
{"id": "cavity_magnetron", "name": "Cavity magnetron", "year": 1940, "cat": "electronics", "wiki": "Cavity magnetron", "req": ["vacuum_tube", "electromagnet"], "desc": "A tube generating high-power microwaves in resonant cavities, which made compact radar and microwave ovens possible."},
{"id": "doping", "name": "Semiconductor doping", "year": 1940, "cat": "electronics", "wiki": "Doping (semiconductor)", "req": ["semiconductor"], "desc": "Adding trace impurities to a semiconductor to control whether it carries electrons or holes."},
{"id": "pn_junction", "name": "p–n junction", "year": 1940, "cat": "electronics", "wiki": "P–n junction", "req": ["doping"], "desc": "The boundary between p- and n-type semiconductor, discovered by Ohl; the basis of diodes, transistors and solar cells."},
{"id": "op_amp", "name": "Operational amplifier", "year": 1941, "cat": "electronics", "wiki": "Operational amplifier", "req": ["differential_amplifier", "negative_feedback_amplifier"], "desc": "A high-gain DC amplifier configured by feedback to add, integrate or filter; later the most common analog IC."},
{"id": "traveling_wave_tube", "name": "Traveling-wave tube", "year": 1943, "cat": "electronics", "wiki": "Traveling-wave tube", "req": ["klystron"], "desc": "A broadband microwave amplifier tube still used in satellite transponders and radar."},
{"id": "point_contact_transistor", "name": "Point-contact transistor", "year": 1947, "cat": "electronics", "wiki": "Point-contact transistor", "req": ["crystal_detector", "semiconductor", "vacuum_tube"], "desc": "Bardeen and Brattain's first working transistor, two gold contacts on germanium."},
{"id": "zener_diode", "name": "Zener diode", "year": 1950, "cat": "electronics", "wiki": "Zener diode", "req": ["pn_junction"], "desc": "A diode designed to conduct in reverse at a set voltage, used as a voltage reference and regulator."},
{"id": "photodiode", "name": "Photodiode", "year": 1950, "cat": "electronics", "wiki": "Photodiode", "req": ["pn_junction", "photoconductivity"], "desc": "A p–n junction that converts light into current, used in optical sensing and communication."},
{"id": "bipolar_junction_transistor", "name": "Bipolar junction transistor", "year": 1951, "cat": "electronics", "wiki": "Bipolar junction transistor", "req": ["transistor", "pn_junction"], "desc": "Shockley's sandwich transistor of p- and n-layers, the mainstay of early solid-state electronics."},
{"id": "zone_melting", "name": "Zone melting", "year": 1951, "cat": "electronics", "wiki": "Zone melting", "req": ["semiconductor", "transistor"], "desc": "Pfann's method of purifying crystals by sweeping a molten zone, which produced ultrapure germanium and silicon."},
{"id": "avalanche_photodiode", "name": "Avalanche photodiode", "year": 1952, "cat": "electronics", "wiki": "Avalanche photodiode", "req": ["photodiode"], "desc": "A photodiode with internal gain from avalanche multiplication, used in fiber optics and lidar."},
{"id": "jfet", "name": "JFET", "year": 1953, "cat": "electronics", "wiki": "JFET", "req": ["field_effect_transistor", "pn_junction"], "desc": "The junction-gate field-effect transistor, the first practical FET."},
{"id": "analog_to_digital_converter", "name": "Analog-to-digital converter", "year": 1954, "cat": "electronics", "wiki": "Analog-to-digital converter", "req": ["vacuum_tube", "flip_flop"], "desc": "A circuit that turns continuous voltages into numbers, linking the physical world to digital processing."},
{"id": "nixie_tube", "name": "Nixie tube", "year": 1955, "cat": "electronics", "wiki": "Nixie tube", "req": ["neon_lamp"], "desc": "A neon glow tube with stacked digit-shaped cathodes, the standard numeric display before LEDs."},
{"id": "thyristor", "name": "Thyristor", "year": 1956, "cat": "electronics", "wiki": "Thyristor", "req": ["bipolar_junction_transistor", "pn_junction"], "desc": "A four-layer silicon switch (SCR) that latches on, replacing mercury-arc valves in power control."},
{"id": "supercapacitor", "name": "Supercapacitor", "year": 1957, "cat": "electronics", "wiki": "Supercapacitor", "req": ["electrolytic_capacitor", "lead_acid_battery", "modern_chemistry"], "desc": "A double-layer capacitor with very high capacitance that bridges capacitors and batteries."},
{"id": "thermal_oxidation", "name": "Thermal oxidation of silicon", "year": 1957, "cat": "electronics", "wiki": "Thermal oxidation", "req": ["semiconductor"], "desc": "Growing a protective silicon dioxide layer on silicon, which passivated surfaces and masked diffusion."},
{"id": "tunnel_diode", "name": "Tunnel diode", "year": 1957, "cat": "electronics", "wiki": "Tunnel diode", "req": ["pn_junction", "quantum_mechanics"], "desc": "Esaki's heavily doped diode that uses quantum tunneling for very fast switching."},
{"id": "wire_bonding", "name": "Wire bonding", "year": 1957, "cat": "electronics", "wiki": "Wire bonding", "req": ["transistor"], "desc": "Connecting a chip to its package with fine gold or aluminium wires."},
{"id": "halogen_lamp", "name": "Halogen lamp", "year": 1959, "cat": "electronics", "wiki": "Halogen lamp", "req": ["light_bulb"], "desc": "An incandescent lamp with halogen gas that redeposits tungsten, giving brighter, longer-lived light."},
{"id": "switched_mode_power_supply", "name": "Switched-mode power supply", "year": 1959, "cat": "electronics", "wiki": "Switched-mode power supply", "req": ["transistor", "transformer"], "desc": "A supply that switches rapidly and filters the result, far more efficient and compact than linear supplies."},
{"id": "planar_process", "name": "Planar process", "year": 1959, "cat": "electronics", "wiki": "Planar process", "req": ["thermal_oxidation", "photolithography", "doping", "monocrystalline_silicon"], "desc": "Hoerni's method of building transistors under a flat oxide layer, which made monolithic integrated circuits manufacturable."},
{"id": "mosfet", "name": "MOSFET", "year": 1959, "cat": "electronics", "wiki": "MOSFET", "req": ["field_effect_transistor", "thermal_oxidation", "monocrystalline_silicon"], "desc": "Atalla and Kahng's metal-oxide-semiconductor transistor, the most manufactured device in history."},
{"id": "epitaxy", "name": "Epitaxy", "year": 1960, "cat": "electronics", "wiki": "Epitaxy", "req": ["chemical_vapor_deposition", "semiconductor"], "desc": "Growing a crystalline layer aligned with a substrate, giving controlled device layers."},
{"id": "brushless_dc_motor", "name": "Brushless DC motor", "year": 1962, "cat": "electronics", "wiki": "Brushless DC electric motor", "req": ["electric_motor", "transistor", "hall_effect"], "desc": "A motor commutated electronically rather than by brushes, used in drives, fans and drones."},
{"id": "light_emitting_diode", "name": "Light-emitting diode", "year": 1962, "cat": "electronics", "wiki": "Light-emitting diode", "req": ["pn_junction", "electroluminescence", "gallium_arsenide"], "desc": "A diode that emits light when current flows; Holonyak's red LED of 1962 began solid-state lighting."},
{"id": "laser_diode", "name": "Laser diode", "year": 1962, "cat": "electronics", "wiki": "Laser diode", "req": ["laser", "light_emitting_diode", "gallium_arsenide"], "desc": "A semiconductor laser in a p–n junction, now used in fiber optics, optical discs and barcode readers."},
{"id": "thin_film_transistor", "name": "Thin-film transistor", "year": 1962, "cat": "electronics", "wiki": "Thin-film transistor", "req": ["mosfet"], "desc": "A transistor deposited as thin films on glass, used to drive pixels in flat-panel displays."},
{"id": "cmos", "name": "CMOS", "year": 1963, "cat": "electronics", "wiki": "CMOS", "req": ["mosfet"], "desc": "Complementary pairs of n- and p-type MOSFETs that draw power only when switching; the basis of nearly all modern chips."},
{"id": "ttl", "name": "Transistor-transistor logic", "year": 1963, "cat": "electronics", "wiki": "Transistor–transistor logic", "req": ["bipolar_junction_transistor", "integrated_circuit"], "desc": "A bipolar logic family that became the standard building block of digital systems in the 1960s and 1970s."},
{"id": "opto_isolator", "name": "Opto-isolator", "year": 1963, "cat": "electronics", "wiki": "Opto-isolator", "req": ["light_emitting_diode", "photodiode"], "desc": "An LED and photodetector in one package that pass signals while electrically isolating circuits."},
{"id": "dual_in_line_package", "name": "Dual in-line package", "year": 1964, "cat": "electronics", "wiki": "Dual in-line package", "req": ["integrated_circuit", "printed_circuit_board"], "desc": "The rectangular chip package with two rows of pins, standard for decades."},
{"id": "flip_chip", "name": "Flip chip", "year": 1964, "cat": "electronics", "wiki": "Flip chip", "req": ["integrated_circuit"], "desc": "Mounting a die face down on solder bumps for short, dense connections."},
{"id": "plasma_display", "name": "Plasma display", "year": 1964, "cat": "electronics", "wiki": "Plasma display", "req": ["neon_lamp"], "desc": "A panel of tiny gas cells glowing like neon lamps, used for early terminals and large flat TVs."},
{"id": "moores_law", "name": "Moore's law", "year": 1965, "cat": "electronics", "wiki": "Moore's law", "req": ["integrated_circuit"], "desc": "Moore's observation that transistor counts per chip double regularly, which guided the industry for decades."},
{"id": "hall_effect_sensor", "name": "Hall effect sensor", "year": 1965, "cat": "electronics", "wiki": "Hall-effect sensor", "req": ["hall_effect", "integrated_circuit"], "desc": "A semiconductor sensor that measures magnetic fields, used for position, speed and current sensing."},
{"id": "surface_mount_technology", "name": "Surface-mount technology", "year": 1965, "cat": "electronics", "wiki": "Surface-mount technology", "req": ["printed_circuit_board", "integrated_circuit"], "desc": "Soldering components directly onto board surfaces instead of through holes, enabling small, automated assembly."},
{"id": "self_aligned_gate", "name": "Self-aligned gate", "year": 1966, "cat": "electronics", "wiki": "Self-aligned gate", "req": ["mosfet"], "desc": "Using the gate itself as a mask for source and drain doping; with silicon gates it made MOS chips fast and dense."},
{"id": "vacuum_fluorescent_display", "name": "Vacuum fluorescent display", "year": 1967, "cat": "electronics", "wiki": "Vacuum fluorescent display", "req": ["vacuum_tube", "seven_segment_display"], "desc": "A phosphor-coated anode display lit by electrons from a filament, common in calculators and appliances."},
{"id": "floating_gate_mosfet", "name": "Floating-gate MOSFET", "year": 1967, "cat": "electronics", "wiki": "Floating-gate MOSFET", "req": ["mosfet"], "desc": "A MOSFET with an isolated gate that traps charge for years, the storage cell of nonvolatile memory."},
{"id": "mems", "name": "MEMS", "year": 1967, "cat": "electronics", "wiki": "MEMS", "req": ["integrated_circuit", "photolithography"], "desc": "Microscopic mechanical structures made with chip fabrication methods, used in sensors and actuators."},
{"id": "variable_frequency_drive", "name": "Variable-frequency drive", "year": 1968, "cat": "electronics", "wiki": "Variable-frequency drive", "req": ["induction_motor", "thyristor", "power_inverter"], "desc": "Electronics that vary supply frequency to control AC motor speed, saving large amounts of energy."},
{"id": "molecular_beam_epitaxy", "name": "Molecular-beam epitaxy", "year": 1968, "cat": "electronics", "wiki": "Molecular-beam epitaxy", "req": ["epitaxy", "vacuum_pump", "gallium_arsenide"], "desc": "Growing crystals one atomic layer at a time in ultra-high vacuum, enabling quantum wells and HEMTs."},
{"id": "liquid_crystal_display", "name": "Liquid-crystal display", "year": 1968, "cat": "electronics", "wiki": "Liquid-crystal display", "req": ["liquid_crystal", "integrated_circuit"], "desc": "A flat display that switches liquid crystals with voltage to modulate light; low power and thin."},
{"id": "ion_implantation", "name": "Ion implantation", "year": 1970, "cat": "electronics", "wiki": "Ion implantation", "req": ["doping", "vacuum_pump"], "desc": "Firing accelerated dopant ions into silicon for precise, uniform doping."},
{"id": "resistive_touchscreen", "name": "Resistive touchscreen", "year": 1971, "cat": "electronics", "wiki": "Resistive touchscreen", "req": ["touchscreen", "resistor"], "desc": "Hurst's two conductive layers that register touch where they are pressed together."},
{"id": "tft_lcd", "name": "Active-matrix LCD", "year": 1972, "cat": "electronics", "wiki": "TFT LCD", "req": ["liquid_crystal_display", "thin_film_transistor"], "desc": "An LCD with a transistor at each pixel, enabling laptop screens and flat-panel TVs."},
{"id": "reactive_ion_etching", "name": "Reactive-ion etching", "year": 1974, "cat": "electronics", "wiki": "Reactive-ion etching", "req": ["photolithography", "vacuum_pump"], "desc": "Plasma etching that cuts vertical features precisely, enabling ever-smaller chip patterns."},
{"id": "dennard_scaling", "name": "Dennard scaling", "year": 1974, "cat": "electronics", "wiki": "Dennard scaling", "req": ["mosfet", "moores_law"], "desc": "The rule that shrinking MOSFETs keeps power density constant, which drove chip speed gains until about 2006."},
{"id": "atomic_layer_deposition", "name": "Atomic layer deposition", "year": 1974, "cat": "electronics", "wiki": "Atomic layer deposition", "req": ["chemical_vapor_deposition", "vacuum_pump", "catalysis"], "desc": "Depositing films one atomic layer per cycle with self-limiting reactions, vital for high-k gates and 3D memory."},
{"id": "electronic_paper", "name": "Electronic paper", "year": 1974, "cat": "electronics", "wiki": "Electronic paper", "req": ["liquid_crystal_display"], "desc": "Reflective displays that mimic ink on paper and hold an image without power, used in e-readers."},
{"id": "power_mosfet", "name": "Power MOSFET", "year": 1976, "cat": "electronics", "wiki": "Power MOSFET", "req": ["mosfet"], "desc": "A MOSFET built to switch large currents quickly, the basis of efficient power supplies."},
{"id": "eeprom", "name": "EEPROM", "year": 1978, "cat": "electronics", "wiki": "EEPROM", "req": ["eprom"], "desc": "Electrically erasable programmable memory that can be rewritten in circuit."},
{"id": "stepper", "name": "Wafer stepper", "year": 1978, "cat": "electronics", "wiki": "Stepper", "req": ["photolithography"], "desc": "A lithography machine that exposes a chip pattern repeatedly across a wafer with reduction optics."},
{"id": "hemt", "name": "High-electron-mobility transistor", "year": 1979, "cat": "electronics", "wiki": "High-electron-mobility transistor", "req": ["molecular_beam_epitaxy", "field_effect_transistor"], "desc": "A heterojunction FET with very fast electrons; in gallium nitride it became a key RF and power device."},
{"id": "compact_fluorescent", "name": "Compact fluorescent lamp", "year": 1980, "cat": "electronics", "wiki": "Compact fluorescent lamp", "req": ["fluorescent_lamp", "switched_mode_power_supply"], "desc": "A folded fluorescent tube with an electronic ballast that fits standard bulb sockets."},
{"id": "quantum_dot", "name": "Quantum dot", "year": 1981, "cat": "electronics", "wiki": "Quantum dot", "req": ["semiconductor", "quantum_mechanics"], "desc": "Nanocrystals whose emission color depends on size, used in displays and imaging."},
{"id": "igbt", "name": "IGBT", "year": 1982, "cat": "electronics", "wiki": "Insulated-gate bipolar transistor", "req": ["power_mosfet", "thyristor"], "desc": "A MOS-gated bipolar power switch that handles high voltage efficiently; key to electric trains, EVs and inverters."},
{"id": "excimer_laser_lithography", "name": "Excimer laser lithography", "year": 1982, "cat": "electronics", "wiki": "Excimer laser", "req": ["laser", "stepper"], "desc": "Deep-ultraviolet lithography with excimer lasers, which carried chip scaling for decades."},
{"id": "capacitive_touchscreen", "name": "Projected capacitive touchscreen", "year": 1984, "cat": "electronics", "wiki": "Capacitive sensing", "req": ["touchscreen", "integrated_circuit"], "desc": "A grid of electrodes that senses the capacitance of fingers through glass, standard on smartphones."},
{"id": "chemical_mechanical_polishing", "name": "Chemical-mechanical polishing", "year": 1985, "cat": "electronics", "wiki": "Chemical-mechanical polishing", "req": ["integrated_circuit"], "desc": "Flattening wafers with abrasive slurry and chemistry, making many-layer wiring possible."},
{"id": "digital_micromirror_device", "name": "Digital micromirror device", "year": 1987, "cat": "electronics", "wiki": "Digital micromirror device", "req": ["mems", "cmos"], "desc": "A chip with millions of tilting mirrors that forms images in DLP projectors."},
{"id": "oled", "name": "OLED", "year": 1987, "cat": "electronics", "wiki": "OLED", "req": ["light_emitting_diode", "electroluminescence"], "desc": "Tang and VanSlyke's organic light-emitting diode, thin emissive layers that need no backlight."},
{"id": "giant_magnetoresistance", "name": "Giant magnetoresistance", "year": 1988, "cat": "electronics", "wiki": "Giant magnetoresistance", "req": ["molecular_beam_epitaxy"], "desc": "Large resistance changes in magnetic multilayers, which enabled high-density hard-disk read heads and spintronics."},
{"id": "finfet", "name": "FinFET", "year": 1989, "cat": "electronics", "wiki": "Fin field-effect transistor", "req": ["mosfet", "reactive_ion_etching"], "desc": "A transistor whose channel is a vertical fin wrapped by the gate; mass-produced from 2011 to keep scaling going."},
{"id": "ball_grid_array", "name": "Ball grid array", "year": 1989, "cat": "electronics", "wiki": "Ball grid array", "req": ["surface_mount_technology", "flip_chip"], "desc": "A package with solder balls across its underside, allowing hundreds of connections."},
{"id": "blue_led", "name": "Blue LED", "year": 1993, "cat": "electronics", "wiki": "Indium gallium nitride", "req": ["light_emitting_diode", "molecular_beam_epitaxy", "gallium_nitride"], "desc": "Bright gallium nitride blue LEDs by Akasaki, Amano and Nakamura, which made white LED lighting possible."},
{"id": "vibrating_structure_gyroscope", "name": "MEMS gyroscope", "year": 1993, "cat": "electronics", "wiki": "Vibrating structure gyroscope", "req": ["mems", "gyroscope"], "desc": "A tiny vibrating structure that senses rotation through the Coriolis effect, used in phones, cars and drones."},
{"id": "tunnel_magnetoresistance", "name": "Tunnel magnetoresistance", "year": 1995, "cat": "electronics", "wiki": "Tunnel magnetoresistance", "req": ["giant_magnetoresistance", "quantum_mechanics"], "desc": "Spin-dependent tunneling through a thin insulator, used in disk heads and magnetic memory."},
{"id": "white_led", "name": "White LED lamp", "year": 1996, "cat": "electronics", "wiki": "LED lamp", "req": ["blue_led"], "desc": "Blue LEDs with yellow phosphor that produce white light, now replacing most incandescent and fluorescent lamps."},
{"id": "copper_interconnect", "name": "Copper interconnect", "year": 1997, "cat": "electronics", "wiki": "Copper interconnects", "req": ["chemical_mechanical_polishing"], "desc": "Replacing aluminium chip wiring with lower-resistance copper using damascene polishing."},
{"id": "silicon_on_insulator", "name": "Silicon on insulator", "year": 1998, "cat": "electronics", "wiki": "Silicon on insulator", "req": ["mosfet", "thermal_oxidation"], "desc": "Building transistors on a thin silicon layer over oxide to cut leakage and capacitance."},
{"id": "microled", "name": "MicroLED", "year": 2000, "cat": "electronics", "wiki": "MicroLED", "req": ["light_emitting_diode", "blue_led"], "desc": "Arrays of microscopic inorganic LEDs forming pixels, offering bright, durable emissive displays."},
{"id": "wide_bandgap_power", "name": "SiC and GaN power devices", "year": 2001, "cat": "electronics", "wiki": "Wide-bandgap semiconductor", "req": ["schottky_diode", "hemt", "gallium_nitride", "silicon_carbide"], "desc": "Silicon carbide and gallium nitride switches that run hotter, faster and more efficiently than silicon, used in EV chargers and inverters."},
{"id": "amoled", "name": "AMOLED", "year": 2003, "cat": "electronics", "wiki": "AMOLED", "req": ["oled", "thin_film_transistor"], "desc": "OLED displays driven by thin-film transistors, used in most high-end phones."},
{"id": "immersion_lithography", "name": "Immersion lithography", "year": 2006, "cat": "electronics", "wiki": "Immersion lithography", "req": ["excimer_laser_lithography"], "desc": "Lithography through a water layer to sharpen resolution, used to print features below 50 nm."},
{"id": "mram", "name": "MRAM", "year": 2006, "cat": "electronics", "wiki": "Magnetoresistive RAM", "req": ["tunnel_magnetoresistance", "cmos"], "desc": "Nonvolatile memory storing bits in magnetic tunnel junctions, fast and durable."},
{"id": "through_silicon_via", "name": "Through-silicon via", "year": 2006, "cat": "electronics", "wiki": "Through-silicon via", "req": ["reactive_ion_etching"], "desc": "Vertical copper connections through a silicon die that let chips be stacked."},
{"id": "high_k_dielectric", "name": "High-k metal gate", "year": 2007, "cat": "electronics", "wiki": "High-kappa dielectric", "req": ["atomic_layer_deposition", "mosfet"], "desc": "Replacing silicon dioxide gate insulators with hafnium oxide to stop leakage at small sizes."},
{"id": "memristor", "name": "Memristor", "year": 2008, "cat": "electronics", "wiki": "Memristor", "req": ["resistor", "atomic_layer_deposition"], "desc": "A resistor whose value remembers past current, demonstrated in titanium oxide and studied for memory and neural hardware."},
{"id": "quantum_dot_display", "name": "Quantum dot display", "year": 2013, "cat": "electronics", "wiki": "Quantum dot display", "req": ["quantum_dot", "tft_lcd"], "desc": "Displays using quantum dots to convert backlight into pure colors for wider color range."},
{"id": "high_bandwidth_memory", "name": "High Bandwidth Memory", "year": 2015, "cat": "electronics", "wiki": "High Bandwidth Memory", "req": ["dram", "through_silicon_via"], "desc": "Stacked DRAM dies linked by through-silicon vias beside a processor, crucial for GPUs and AI accelerators."},
{"id": "chiplet", "name": "Chiplet", "year": 2017, "cat": "electronics", "wiki": "Chiplet", "req": ["integrated_circuit", "flip_chip"], "desc": "Building a processor from several smaller dies in one package, improving yield and mixing process nodes."},
{"id": "euv_lithography", "name": "EUV lithography", "year": 2019, "cat": "electronics", "wiki": "EUV lithography", "req": ["immersion_lithography", "laser"], "desc": "Lithography with 13.5 nm light from tin plasma and mirror optics, used in volume production from 2019."},
{"id": "gaafet", "name": "Gate-all-around FET", "year": 2022, "cat": "electronics", "wiki": "Multigate device", "req": ["finfet", "atomic_layer_deposition"], "desc": "Transistors whose gate surrounds stacked nanosheet channels, in mass production from 2022 at the 3 nm node."},
{"id": "working_animal", "name": "Draft animal power", "year": -4000, "cat": "energy", "wiki": "Working animal", "req": ["domestication_of_animals"], "desc": "Oxen, horses and donkeys harnessed to pull, carry and turn machinery, the main non-human power source for millennia."},
{"id": "horse_mill", "name": "Horse mill", "year": -300, "cat": "energy", "wiki": "Horse mill", "req": ["working_animal"], "desc": "A mill turned by animals walking in a circle, used to grind grain and later to drive pumps and early factories."},
{"id": "treadwheel", "name": "Treadwheel", "year": -300, "cat": "energy", "wiki": "Treadwheel", "req": ["wheel", "pulley"], "desc": "A large wheel turned by people or animals walking inside it, used to power cranes, pumps and mills."},
{"id": "watermill", "name": "Watermill", "year": -250, "cat": "energy", "wiki": "Watermill", "req": ["water_wheel", "gear"], "desc": "A mill using a water wheel and gearing to grind grain or drive other machinery."},
{"id": "ship_mill", "name": "Ship mill", "year": 537, "cat": "energy", "wiki": "Ship mill", "req": ["watermill"], "desc": "A watermill mounted on a moored boat so its wheel sits in a river current."},
{"id": "tide_mill", "name": "Tide mill", "year": 619, "cat": "energy", "wiki": "Tide mill", "req": ["watermill"], "desc": "A watermill driven by tidal water impounded behind a dam and released on the ebb."},
{"id": "panemone_windmill", "name": "Panemone windmill", "year": 644, "cat": "energy", "wiki": "Panemone windmill", "req": ["windmill"], "desc": "A vertical-shaft windmill with sails rotating horizontally, the type built in medieval Persia."},
{"id": "post_mill", "name": "Post mill", "year": 1180, "cat": "energy", "wiki": "Post mill", "req": ["windmill"], "desc": "The earliest European horizontal-axis windmill, whose whole body turns on a central post to face the wind."},
{"id": "tower_mill", "name": "Tower mill", "year": 1300, "cat": "energy", "wiki": "Tower mill", "req": ["post_mill"], "desc": "A windmill with a fixed masonry tower and a rotating cap carrying the sails, allowing larger mills."},
{"id": "smock_mill", "name": "Smock mill", "year": 1600, "cat": "energy", "wiki": "Smock mill", "req": ["tower_mill"], "desc": "A tower-type windmill with a timber-framed, usually octagonal body and a rotating cap."},
{"id": "trompe", "name": "Trompe", "year": 1640, "cat": "energy", "wiki": "Trompe", "req": ["watermill"], "desc": "A water-powered air compressor with no moving parts, used to blow forges and later to drive mine machinery."},
{"id": "aeolipile", "name": "Aeolipile", "year": 50, "cat": "energy", "wiki": "Aeolipile", "req": ["bronze", "control_of_fire"], "desc": "Hero of Alexandria's spinning steam-jet sphere, the first recorded device turning steam into rotary motion."},
{"id": "hydraulic_ram", "name": "Hydraulic ram", "year": 1796, "cat": "energy", "wiki": "Hydraulic ram", "req": ["water_wheel", "classical_mechanics"], "desc": "A self-acting pump that uses the water-hammer effect of falling water to lift part of it higher."},
{"id": "line_shaft", "name": "Line shaft", "year": 1780, "cat": "energy", "wiki": "Line shaft", "req": ["water_wheel", "factory_system", "belt_drive", "watt_steam_engine"], "desc": "Overhead rotating shafts and belts that distributed power from one prime mover to many factory machines."},
{"id": "hydraulic_accumulator", "name": "Hydraulic accumulator", "year": 1850, "cat": "energy", "wiki": "Hydraulic accumulator", "req": ["steam_engine", "cast_iron"], "desc": "Armstrong's weighted ram storing water under pressure, which made hydraulic power networks practical."},
{"id": "hydraulic_power_network", "name": "Hydraulic power network", "year": 1868, "cat": "energy", "wiki": "Hydraulic power network", "req": ["hydraulic_accumulator", "pipeline"], "desc": "City-wide networks of high-pressure water mains that powered lifts, cranes and presses before electricity."},
{"id": "steam_digester", "name": "Steam digester", "year": 1679, "cat": "energy", "wiki": "Steam digester", "req": ["vacuum_pump"], "desc": "Denis Papin's pressure cooker, which pointed toward steam power and introduced the safety valve."},
{"id": "safety_valve", "name": "Safety valve", "year": 1679, "cat": "energy", "wiki": "Safety valve", "req": ["steam_digester"], "desc": "A valve that opens automatically at a set pressure, invented for Papin's digester and essential to every boiler."},
{"id": "beam_engine", "name": "Beam engine", "year": 1712, "cat": "energy", "wiki": "Beam engine", "req": ["steam_engine"], "desc": "A steam engine transmitting piston force through a rocking overhead beam, the form of Newcomen and Watt engines."},
{"id": "centrifugal_governor", "name": "Centrifugal governor", "year": 1788, "cat": "energy", "wiki": "Centrifugal governor", "req": ["watt_steam_engine"], "desc": "Spinning flyballs that throttle an engine to hold its speed constant, an early feedback controller."},
{"id": "compound_engine", "name": "Compound steam engine", "year": 1804, "cat": "energy", "wiki": "Compound steam engine", "req": ["watt_steam_engine"], "desc": "An engine expanding steam in successive cylinders, greatly improving fuel efficiency."},
{"id": "flued_boiler", "name": "Flued boiler", "year": 1812, "cat": "energy", "wiki": "Flued boiler", "req": ["watt_steam_engine", "safety_valve"], "desc": "A cylindrical shell boiler with internal furnace flues (Cornish and Lancashire types) that made high-pressure steam practical."},
{"id": "cornish_engine", "name": "Cornish engine", "year": 1812, "cat": "energy", "wiki": "Cornish engine", "req": ["watt_steam_engine", "flued_boiler"], "desc": "Trevithick's high-pressure, expansive-working beam engine for mine pumping, far more economical than Watt's."},
{"id": "fire_tube_boiler", "name": "Fire-tube boiler", "year": 1829, "cat": "energy", "wiki": "Fire-tube boiler", "req": ["flued_boiler"], "desc": "A boiler in which hot gases pass through many tubes immersed in water, standard on locomotives."},
{"id": "surface_condenser", "name": "Surface condenser", "year": 1834, "cat": "energy", "wiki": "Surface condenser", "req": ["watt_steam_engine"], "desc": "A heat exchanger that condenses exhaust steam without mixing, returning pure water to the boiler."},
{"id": "portable_engine", "name": "Portable engine", "year": 1839, "cat": "energy", "wiki": "Portable engine", "req": ["fire_tube_boiler"], "desc": "A wheeled steam engine hauled to farms and works to drive threshers and saws."},
{"id": "economiser", "name": "Economiser", "year": 1845, "cat": "energy", "wiki": "Economizer", "req": ["flued_boiler"], "desc": "Green's heat exchanger using flue gas to preheat boiler feedwater, cutting fuel use."},
{"id": "corliss_engine", "name": "Corliss steam engine", "year": 1849, "cat": "energy", "wiki": "Corliss steam engine", "req": ["compound_engine", "centrifugal_governor"], "desc": "A stationary engine with rotary valves and variable cutoff that set new standards of efficiency and speed regulation."},
{"id": "superheater", "name": "Superheater", "year": 1850, "cat": "energy", "wiki": "Superheater", "req": ["flued_boiler"], "desc": "A device that heats steam above its boiling point, raising engine and turbine efficiency."},
{"id": "feedwater_heater", "name": "Feedwater heater", "year": 1850, "cat": "energy", "wiki": "Feedwater heater", "req": ["surface_condenser"], "desc": "Preheating boiler water with bled or exhaust steam to raise plant efficiency."},
{"id": "injector", "name": "Injector", "year": 1858, "cat": "energy", "wiki": "Injector", "req": ["fire_tube_boiler"], "desc": "Giffard's steam-driven jet pump for forcing feedwater into a boiler with no moving parts."},
{"id": "rankine_cycle", "name": "Rankine cycle", "year": 1859, "cat": "energy", "wiki": "Rankine cycle", "req": ["thermodynamics", "watt_steam_engine"], "desc": "The idealised vapour power cycle describing steam engines and turbine power plants."},
{"id": "water_tube_boiler", "name": "Water-tube boiler", "year": 1867, "cat": "energy", "wiki": "Water-tube boiler", "req": ["flued_boiler", "steel"], "desc": "A boiler with water inside tubes heated by external fire, allowing much higher pressures and outputs."},
{"id": "brayton_cycle", "name": "Brayton cycle", "year": 1872, "cat": "energy", "wiki": "Brayton cycle", "req": ["thermodynamics"], "desc": "The constant-pressure heat-addition cycle underlying gas turbines and jet engines."},
{"id": "steam_turbine", "name": "Steam turbine", "year": 1884, "cat": "energy", "wiki": "Steam turbine", "req": ["watt_steam_engine", "thermodynamics"], "desc": "Parsons's multi-stage turbine converting steam's energy directly into rotation, now the main generator drive."},
{"id": "uniflow_engine", "name": "Uniflow steam engine", "year": 1908, "cat": "energy", "wiki": "Uniflow steam engine", "req": ["compound_engine"], "desc": "An engine in which steam flows one way through the cylinder, reducing heat losses."},
{"id": "tesla_turbine", "name": "Tesla turbine", "year": 1913, "cat": "energy", "wiki": "Tesla turbine", "req": ["steam_turbine"], "desc": "A bladeless turbine driven by fluid friction on closely spaced discs."},
{"id": "pulverized_coal_boiler", "name": "Pulverized coal-fired boiler", "year": 1918, "cat": "energy", "wiki": "Pulverized coal-fired boiler", "req": ["water_tube_boiler", "coal_mining"], "desc": "A boiler burning finely ground coal blown into the furnace, the basis of large coal power stations."},
{"id": "supercritical_steam_generator", "name": "Supercritical steam generator", "year": 1957, "cat": "energy", "wiki": "Supercritical steam generator", "req": ["water_tube_boiler", "steam_turbine"], "desc": "A boiler operating above water's critical point, raising the efficiency of thermal power plants."},
{"id": "organic_rankine_cycle", "name": "Organic Rankine cycle", "year": 1961, "cat": "energy", "wiki": "Organic Rankine cycle", "req": ["rankine_cycle", "refrigeration"], "desc": "A Rankine cycle using an organic working fluid to make power from low-temperature heat."},
{"id": "water_turbine", "name": "Water turbine", "year": 1827, "cat": "energy", "wiki": "Water turbine", "req": ["water_wheel", "classical_mechanics"], "desc": "An enclosed rotary machine extracting energy from flowing water, far more compact and efficient than a wheel."},
{"id": "francis_turbine", "name": "Francis turbine", "year": 1849, "cat": "energy", "wiki": "Francis turbine", "req": ["water_turbine"], "desc": "An inward-flow reaction turbine for medium heads, the most widely used hydro turbine."},
{"id": "pelton_wheel", "name": "Pelton wheel", "year": 1879, "cat": "energy", "wiki": "Pelton wheel", "req": ["water_turbine"], "desc": "An impulse turbine with split buckets struck by water jets, suited to very high heads."},
{"id": "cross_flow_turbine", "name": "Cross-flow turbine", "year": 1903, "cat": "energy", "wiki": "Cross-flow turbine", "req": ["water_turbine"], "desc": "A drum-shaped turbine through which water passes twice, popular for small hydro schemes."},
{"id": "kaplan_turbine", "name": "Kaplan turbine", "year": 1913, "cat": "energy", "wiki": "Kaplan turbine", "req": ["francis_turbine"], "desc": "A propeller turbine with adjustable blades for low heads and large flows."},
{"id": "turgo_turbine", "name": "Turgo turbine", "year": 1919, "cat": "energy", "wiki": "Turgo turbine", "req": ["pelton_wheel"], "desc": "An impulse turbine with jets striking the runner at an angle, for medium-high heads."},
{"id": "hydroelectricity", "name": "Hydroelectricity", "year": 1878, "cat": "energy", "wiki": "Hydroelectricity", "req": ["water_turbine", "electric_generator"], "desc": "Generating electricity from falling or flowing water, first at Cragside and soon in public plants."},
{"id": "run_of_river_hydro", "name": "Run-of-the-river hydroelectricity", "year": 1882, "cat": "energy", "wiki": "Run-of-the-river hydroelectricity", "req": ["hydroelectricity"], "desc": "Hydro plants that use river flow with little or no storage reservoir."},
{"id": "adams_power_plant", "name": "Niagara Falls Adams power plant", "year": 1895, "cat": "energy", "wiki": "Adams Power Plant Transformer House", "req": ["hydroelectricity", "polyphase_system"], "desc": "The first large-scale AC hydroelectric plant, sending Niagara power to Buffalo and proving long-distance AC."},
{"id": "pumped_storage", "name": "Pumped-storage hydroelectricity", "year": 1907, "cat": "energy", "wiki": "Pumped-storage hydroelectricity", "req": ["hydroelectricity", "electric_motor"], "desc": "Storing energy by pumping water uphill and releasing it through turbines, still the largest form of grid storage."},
{"id": "three_gorges_dam", "name": "Three Gorges Dam", "year": 2012, "cat": "energy", "wiki": "Three Gorges Dam", "req": ["hoover_dam", "hydroelectricity", "gravity_dam"], "desc": "The world's largest power station by installed capacity, on the Yangtze River."},
{"id": "power_station", "name": "Power station", "year": 1881, "cat": "energy", "wiki": "Power station", "req": ["dynamo", "watt_steam_engine"], "desc": "A central plant generating electricity for many customers; Godalming and Pearl Street led the way in 1881-82."},
{"id": "pearl_street_station", "name": "Pearl Street Station", "year": 1882, "cat": "energy", "wiki": "Pearl Street Station", "req": ["power_station"], "desc": "Edison's first commercial central station in Manhattan, supplying DC light and power by underground mains."},
{"id": "electric_power_transmission", "name": "Electric power transmission", "year": 1882, "cat": "energy", "wiki": "Electric power transmission", "req": ["electrical_grid"], "desc": "Moving bulk electricity over long distances by high-voltage lines from generators to load centres."},
{"id": "electric_power_distribution", "name": "Electric power distribution", "year": 1882, "cat": "energy", "wiki": "Electric power distribution", "req": ["electrical_grid"], "desc": "The final stage of supply, carrying power from substations to consumers at lower voltages."},
{"id": "overhead_power_line", "name": "Overhead power line", "year": 1882, "cat": "energy", "wiki": "Overhead power line", "req": ["electric_power_transmission"], "desc": "Bare conductors suspended from towers or poles, the cheapest way to carry bulk power."},
{"id": "cogeneration", "name": "Cogeneration", "year": 1882, "cat": "energy", "wiki": "Cogeneration", "req": ["power_station"], "desc": "Using a power plant's waste heat for heating or industry, raising total fuel efficiency."},
{"id": "electricity_meter", "name": "Electricity meter", "year": 1888, "cat": "energy", "wiki": "Electricity meter", "req": ["alternating_current"], "desc": "A device measuring electrical energy consumed, which made metered retail electricity possible."},
{"id": "three_phase_power", "name": "Three-phase electric power", "year": 1891, "cat": "energy", "wiki": "Three-phase electric power", "req": ["polyphase_system", "electric_power_transmission"], "desc": "The three-phase AC standard, demonstrated over 175 km from Lauffen to Frankfurt and now universal."},
{"id": "substation", "name": "Electrical substation", "year": 1890, "cat": "energy", "wiki": "Substation", "req": ["transformer", "electric_power_transmission"], "desc": "A facility that switches circuits and transforms voltage between transmission and distribution networks."},
{"id": "electrostatic_precipitator", "name": "Electrostatic precipitator", "year": 1907, "cat": "energy", "wiki": "Electrostatic precipitator", "req": ["alternating_current"], "desc": "Cottrell's device removing fly ash and dust from flue gas with electric charge."},
{"id": "hvdc", "name": "High-voltage direct current", "year": 1954, "cat": "energy", "wiki": "High-voltage direct current", "req": ["mercury_arc_valve", "electric_power_transmission"], "desc": "DC transmission for long distances and undersea cables with lower losses than AC, first commercial at Gotland."},
{"id": "submarine_power_cable", "name": "Submarine power cable", "year": 1954, "cat": "energy", "wiki": "Submarine power cable", "req": ["electric_power_transmission", "hvdc"], "desc": "An insulated cable laid on the seabed to carry power to islands and offshore farms."},
{"id": "combined_cycle", "name": "Combined-cycle power plant", "year": 1960, "cat": "energy", "wiki": "Combined-cycle power plant", "req": ["gas_turbine", "steam_turbine"], "desc": "A plant feeding gas-turbine exhaust heat to a steam turbine, reaching over 60 percent efficiency."},
{"id": "static_var_compensator", "name": "Static VAR compensator", "year": 1974, "cat": "energy", "wiki": "Static VAR compensator", "req": ["substation", "transistor", "thyristor"], "desc": "Thyristor-switched reactors and capacitors that regulate grid voltage and reactive power."},
{"id": "smes", "name": "Superconducting magnetic energy storage", "year": 1974, "cat": "energy", "wiki": "Superconducting magnetic energy storage", "req": ["electromagnet", "electrical_grid", "superconducting_magnet", "niobium_titanium"], "desc": "Storing energy in the magnetic field of a superconducting coil for near-instant release."},
{"id": "demand_response", "name": "Demand response", "year": 1975, "cat": "energy", "wiki": "Demand response", "req": ["electrical_grid", "electricity_meter"], "desc": "Shifting or curtailing consumer electricity use in response to grid conditions or prices."},
{"id": "facts", "name": "Flexible AC transmission system", "year": 1988, "cat": "energy", "wiki": "Flexible AC transmission system", "req": ["static_var_compensator", "thyristor", "igbt"], "desc": "Power-electronic controllers that increase the capacity and controllability of AC lines."},
{"id": "smart_meter", "name": "Smart meter", "year": 2000, "cat": "energy", "wiki": "Smart meter", "req": ["electricity_meter", "microprocessor"], "desc": "A networked meter recording consumption at short intervals and communicating with the utility."},
{"id": "smart_grid", "name": "Smart grid", "year": 2005, "cat": "energy", "wiki": "Smart grid", "req": ["electrical_grid", "smart_meter", "internet"], "desc": "A grid with digital sensing and two-way communication to balance variable supply and demand."},
{"id": "microgrid", "name": "Microgrid", "year": 2005, "cat": "energy", "wiki": "Microgrid", "req": ["smart_grid"], "desc": "A local grid with its own generation and storage that can run connected or islanded."},
{"id": "ev_charging", "name": "Charging station", "year": 1996, "cat": "energy", "wiki": "Charging station", "req": ["electrical_grid", "lead_acid_battery"], "desc": "Public and home equipment for recharging electric vehicles, from early AC posts to modern DC fast chargers."},
{"id": "vehicle_to_grid", "name": "Vehicle-to-grid", "year": 2007, "cat": "energy", "wiki": "Vehicle-to-grid", "req": ["smart_grid", "ev_charging"], "desc": "Using plugged-in electric vehicle batteries to feed power back and stabilise the grid."},
{"id": "virtual_power_plant", "name": "Virtual power plant", "year": 2008, "cat": "energy", "wiki": "Virtual power plant", "req": ["smart_grid", "battery_energy_storage"], "desc": "Software aggregating many small generators, batteries and loads to act as one power plant."},
{"id": "district_heating", "name": "District heating", "year": 1877, "cat": "energy", "wiki": "District heating", "req": ["fire_tube_boiler", "pipeline"], "desc": "Distributing heat from a central plant to many buildings through insulated pipes."},
{"id": "heat_pump", "name": "Heat pump", "year": 1856, "cat": "energy", "wiki": "Heat pump", "req": ["refrigeration", "thermodynamics"], "desc": "A machine moving heat from a cold to a warm space, delivering several units of heat per unit of work."},
{"id": "ground_source_heat_pump", "name": "Ground source heat pump", "year": 1948, "cat": "energy", "wiki": "Ground source heat pump", "req": ["heat_pump"], "desc": "A heat pump exchanging heat with the stable temperature of the ground for efficient heating and cooling."},
{"id": "stirling_engine", "name": "Stirling engine", "year": 1816, "cat": "energy", "wiki": "Stirling engine", "req": ["watt_steam_engine"], "desc": "A closed-cycle external-combustion engine using a regenerator, prized for quiet running and any heat source."},
{"id": "four_stroke_engine", "name": "Four-stroke engine", "year": 1876, "cat": "energy", "wiki": "Four-stroke engine", "req": ["internal_combustion_engine"], "desc": "Otto's compression cycle of intake, compression, power and exhaust, the basis of most piston engines."},
{"id": "two_stroke_engine", "name": "Two-stroke engine", "year": 1878, "cat": "energy", "wiki": "Two-stroke engine", "req": ["internal_combustion_engine"], "desc": "An engine completing its cycle in one revolution, simple and light for small machines."},
{"id": "atkinson_cycle", "name": "Atkinson cycle", "year": 1882, "cat": "energy", "wiki": "Atkinson cycle", "req": ["four_stroke_engine"], "desc": "An engine cycle with a longer expansion than compression stroke, now used in hybrid cars for efficiency."},
{"id": "hot_bulb_engine", "name": "Hot-bulb engine", "year": 1886, "cat": "energy", "wiki": "Hot-bulb engine", "req": ["internal_combustion_engine"], "desc": "A low-compression engine igniting fuel in a heated bulb, widely used in tractors and boats."},
{"id": "diesel_engine", "name": "Diesel engine", "year": 1893, "cat": "energy", "wiki": "Diesel engine", "req": ["four_stroke_engine", "thermodynamics"], "desc": "Rudolf Diesel's compression-ignition engine, the most efficient common heat engine."},
{"id": "wankel_engine", "name": "Wankel engine", "year": 1957, "cat": "energy", "wiki": "Wankel engine", "req": ["four_stroke_engine", "machine_tools"], "desc": "A rotary engine with a triangular rotor in an epitrochoid housing, compact but thirsty."},
{"id": "longwall_mining", "name": "Longwall mining", "year": 1700, "cat": "energy", "wiki": "Longwall mining", "req": ["coal_mining"], "desc": "Extracting coal along a long face in a single slice, mechanised in the 20th century."},
{"id": "coal_gas", "name": "Coal gas", "year": 1792, "cat": "energy", "wiki": "Coal gas", "req": ["coal_mining", "distillation"], "desc": "Fuel gas from heating coal, which lit and heated cities through piped town-gas networks."},
{"id": "gasholder", "name": "Gasholder", "year": 1798, "cat": "energy", "wiki": "Gas holder", "req": ["coal_gas"], "desc": "A large telescoping tank storing town gas at constant pressure for distribution."},
{"id": "davy_lamp", "name": "Davy lamp", "year": 1815, "cat": "energy", "wiki": "Davy lamp", "req": ["coal_mining"], "desc": "A miner's safety lamp whose wire gauze prevented ignition of firedamp, enabling deeper coal mining."},
{"id": "bergius_process", "name": "Bergius process", "year": 1913, "cat": "energy", "wiki": "Bergius process", "req": ["coal_mining", "haber_process", "catalysis", "coke_fuel"], "desc": "Hydrogenating coal under high pressure to make synthetic liquid fuels."},
{"id": "fischer_tropsch", "name": "Fischer–Tropsch process", "year": 1925, "cat": "energy", "wiki": "Fischer–Tropsch process", "req": ["coal_gas", "modern_chemistry", "catalysis", "coke_fuel"], "desc": "Catalytic conversion of carbon monoxide and hydrogen into liquid hydrocarbons, used for coal- and gas-to-liquids."},
{"id": "flue_gas_desulfurization", "name": "Flue-gas desulfurization", "year": 1931, "cat": "energy", "wiki": "Flue-gas desulfurization", "req": ["pulverized_coal_boiler"], "desc": "Scrubbing sulfur dioxide from power-plant exhaust, first at Battersea, to curb acid rain."},
{"id": "underground_coal_gasification", "name": "Underground coal gasification", "year": 1937, "cat": "energy", "wiki": "Underground coal gasification", "req": ["coal_gas", "coal_mining"], "desc": "Gasifying coal in place underground and drawing the syngas to the surface, first in the Soviet Union."},
{"id": "fluidized_bed_combustion", "name": "Fluidized bed combustion", "year": 1968, "cat": "energy", "wiki": "Fluidized bed combustion", "req": ["pulverized_coal_boiler"], "desc": "Burning fuel in a bed of particles suspended by air, allowing low-grade fuels and in-bed sulfur capture."},
{"id": "igcc", "name": "Integrated gasification combined cycle", "year": 1984, "cat": "energy", "wiki": "Integrated gasification combined cycle", "req": ["combined_cycle", "fischer_tropsch"], "desc": "A plant gasifying coal into syngas and burning it in a combined cycle, easing pollutant and CO2 capture."},
{"id": "shale_oil_extraction", "name": "Shale oil extraction", "year": 1837, "cat": "energy", "wiki": "Shale oil extraction", "req": ["distillation"], "desc": "Heating oil shale to release synthetic crude, an industry that predated drilled oil."},
{"id": "kerosene", "name": "Kerosene", "year": 1846, "cat": "energy", "wiki": "Kerosene", "req": ["distillation", "coal_mining"], "desc": "A lamp fuel distilled first from coal and then petroleum, which created the early oil industry."},
{"id": "drilling_rig", "name": "Drilling rig", "year": 1859, "cat": "energy", "wiki": "Drilling rig", "req": ["steam_engine", "steel"], "desc": "Structures and machinery for boring wells deep into the earth, evolving from cable tool to rotary drilling."},
{"id": "pipeline", "name": "Pipeline transport", "year": 1865, "cat": "energy", "wiki": "Pipeline", "req": ["oil_well", "cast_iron"], "desc": "Pipes carrying oil, gas and other fluids over long distances, first built in the Pennsylvania oil fields."},
{"id": "offshore_drilling", "name": "Offshore drilling", "year": 1896, "cat": "energy", "wiki": "Offshore drilling", "req": ["drilling_rig"], "desc": "Drilling for oil beneath the seabed, beginning from piers at Summerland, California."},
{"id": "spindletop", "name": "Spindletop", "year": 1901, "cat": "energy", "wiki": "Spindletop", "req": ["oil_well", "drilling_rig"], "desc": "The Texas gusher drilled with rotary methods that launched the modern petroleum age."},
{"id": "cracking", "name": "Thermal cracking", "year": 1913, "cat": "energy", "wiki": "Cracking (chemistry)", "req": ["oil_refining"], "desc": "Breaking heavy oil molecules into lighter ones such as gasoline, first commercial in the Burton process."},
{"id": "reflection_seismology", "name": "Reflection seismology", "year": 1921, "cat": "energy", "wiki": "Reflection seismology", "req": ["oil_well", "vacuum_tube"], "desc": "Mapping subsurface rock layers with reflected sound waves, the main tool of oil and gas exploration."},
{"id": "blowout_preventer", "name": "Blowout preventer", "year": 1922, "cat": "energy", "wiki": "Blowout preventer", "req": ["drilling_rig"], "desc": "A valve stack that seals a well to stop uncontrolled release of oil or gas."},
{"id": "well_logging", "name": "Well logging", "year": 1927, "cat": "energy", "wiki": "Well logging", "req": ["drilling_rig"], "desc": "Lowering instruments into a borehole to record rock properties, introduced by the Schlumberger brothers."},
{"id": "directional_drilling", "name": "Directional drilling", "year": 1929, "cat": "energy", "wiki": "Directional drilling", "req": ["drilling_rig"], "desc": "Steering a wellbore away from vertical, enabling horizontal wells that run along thin reservoirs."},
{"id": "fluid_catalytic_cracking", "name": "Fluid catalytic cracking", "year": 1942, "cat": "energy", "wiki": "Fluid catalytic cracking", "req": ["cracking", "catalysis"], "desc": "Cracking with a fluidized powdered catalyst, the main way refineries make high-octane gasoline."},
{"id": "oil_platform", "name": "Oil platform", "year": 1947, "cat": "energy", "wiki": "Oil platform", "req": ["offshore_drilling", "steel"], "desc": "A large offshore structure for drilling and producing oil and gas out of sight of land."},
{"id": "fracking", "name": "Hydraulic fracturing", "year": 1947, "cat": "energy", "wiki": "Fracking", "req": ["drilling_rig"], "desc": "Fracturing rock with high-pressure fluid to release oil and gas, transformative when combined with horizontal wells."},
{"id": "catalytic_reforming", "name": "Catalytic reforming", "year": 1949, "cat": "energy", "wiki": "Catalytic reforming", "req": ["oil_refining", "fluid_catalytic_cracking"], "desc": "Converting low-octane naphtha into high-octane reformate over a platinum catalyst, yielding hydrogen too."},
{"id": "enhanced_oil_recovery", "name": "Enhanced oil recovery", "year": 1957, "cat": "energy", "wiki": "Enhanced oil recovery", "req": ["oil_well"], "desc": "Injecting steam, gas or chemicals to recover oil left behind by primary production."},
{"id": "oil_sands", "name": "Oil sands extraction", "year": 1967, "cat": "energy", "wiki": "Oil sands", "req": ["oil_refining"], "desc": "Mining or steaming bitumen out of sand deposits and upgrading it to synthetic crude."},
{"id": "fpso", "name": "FPSO", "year": 1977, "cat": "energy", "wiki": "Floating production storage and offloading", "req": ["oil_platform"], "desc": "A floating vessel that produces, stores and offloads oil, opening deep-water fields."},
{"id": "sagd", "name": "Steam-assisted gravity drainage", "year": 1978, "cat": "energy", "wiki": "Steam-assisted gravity drainage", "req": ["directional_drilling", "enhanced_oil_recovery"], "desc": "Paired horizontal wells inject steam and drain heated bitumen from deep oil sands."},
{"id": "shale_gas", "name": "Shale gas", "year": 1998, "cat": "energy", "wiki": "Shale gas", "req": ["fracking", "directional_drilling"], "desc": "Natural gas from shale made economic by slickwater fracking of horizontal wells, reshaping energy markets."},
{"id": "tight_oil", "name": "Tight oil", "year": 2008, "cat": "energy", "wiki": "Tight oil", "req": ["fracking", "directional_drilling"], "desc": "Light crude produced from low-permeability shale by fracked horizontal wells, as in the Bakken and Permian."},
{"id": "natural_gas", "name": "Natural gas", "year": -200, "cat": "energy", "wiki": "Natural gas", "req": ["iron_working"], "desc": "Methane-rich gas from underground, burned in Han China to boil brine and piped commercially from the 1820s."},
{"id": "lpg", "name": "Liquefied petroleum gas", "year": 1910, "cat": "energy", "wiki": "Liquefied petroleum gas", "req": ["oil_refining"], "desc": "Propane and butane stored as liquid under modest pressure, a portable fuel for cooking and heating."},
{"id": "lng", "name": "Liquefied natural gas", "year": 1917, "cat": "energy", "wiki": "Liquefied natural gas", "req": ["natural_gas", "refrigeration", "liquefaction_of_gases"], "desc": "Natural gas cooled to a liquid for shipping and storage at 1/600 of its volume."},
{"id": "steam_reforming", "name": "Steam reforming", "year": 1926, "cat": "energy", "wiki": "Steam reforming", "req": ["natural_gas", "haber_process"], "desc": "Making hydrogen by reacting methane with steam over a catalyst, the main source of industrial hydrogen."},
{"id": "amine_gas_treating", "name": "Amine gas treating", "year": 1930, "cat": "energy", "wiki": "Amine gas treating", "req": ["natural_gas", "modern_chemistry"], "desc": "Absorbing CO2 and hydrogen sulfide from gas streams with amine solutions, the basis of carbon capture."},
{"id": "compressed_natural_gas", "name": "Compressed natural gas", "year": 1930, "cat": "energy", "wiki": "Compressed natural gas", "req": ["natural_gas"], "desc": "Natural gas stored at high pressure as a vehicle fuel."},
{"id": "lng_carrier", "name": "LNG carrier", "year": 1959, "cat": "energy", "wiki": "LNG carrier", "req": ["lng", "refrigeration", "oil_tanker"], "desc": "A tanker with insulated cryogenic tanks that turned natural gas into a global seaborne commodity."},
{"id": "coalbed_methane", "name": "Coalbed methane", "year": 1980, "cat": "energy", "wiki": "Coalbed methane", "req": ["natural_gas", "fracking"], "desc": "Natural gas recovered from coal seams, developed commercially in the US from the 1980s."},
{"id": "gas_to_liquids", "name": "Gas to liquids", "year": 1993, "cat": "energy", "wiki": "Gas to liquids", "req": ["fischer_tropsch", "natural_gas"], "desc": "Converting natural gas into diesel and other liquid fuels via Fischer–Tropsch synthesis."},
{"id": "heavy_water", "name": "Heavy water production", "year": 1934, "cat": "energy", "wiki": "Heavy water", "req": ["electrolysis_of_water", "isotope"], "desc": "Deuterium oxide concentrated by electrolysis at Vemork, used as a neutron moderator in reactors."},
{"id": "nuclear_reprocessing", "name": "Nuclear reprocessing", "year": 1944, "cat": "energy", "wiki": "Nuclear reprocessing", "req": ["nuclear_reactor"], "desc": "Chemically separating plutonium and uranium from spent fuel, via the PUREX process from 1949."},
{"id": "enriched_uranium", "name": "Uranium enrichment", "year": 1945, "cat": "energy", "wiki": "Enriched uranium", "req": ["nuclear_fission", "isotope", "mass_spectrometry"], "desc": "Raising the fraction of fissile U-235 in uranium, needed for most reactor fuel."},
{"id": "gaseous_diffusion", "name": "Gaseous diffusion", "year": 1945, "cat": "energy", "wiki": "Gaseous diffusion", "req": ["enriched_uranium"], "desc": "Separating uranium isotopes by passing UF6 through porous barriers, as at Oak Ridge K-25."},
{"id": "breeder_reactor", "name": "Breeder reactor", "year": 1951, "cat": "energy", "wiki": "Breeder reactor", "req": ["nuclear_reactor"], "desc": "A reactor producing more fissile fuel than it consumes; EBR-I also made the first nuclear electricity."},
{"id": "nuclear_power_plant", "name": "Nuclear power plant", "year": 1954, "cat": "energy", "wiki": "Nuclear power plant", "req": ["nuclear_reactor", "steam_turbine"], "desc": "A thermal power station heated by fission, first grid-connected at Obninsk in 1954."},
{"id": "pwr", "name": "Pressurized water reactor", "year": 1954, "cat": "energy", "wiki": "Pressurized water reactor", "req": ["nuclear_reactor", "enriched_uranium", "zircaloy"], "desc": "A light-water reactor whose pressurised coolant heats a separate steam loop, the dominant reactor type."},
{"id": "magnox", "name": "Magnox reactor", "year": 1956, "cat": "energy", "wiki": "Magnox", "req": ["nuclear_reactor", "magnesium_alloy"], "desc": "A British gas-cooled, graphite-moderated reactor on natural uranium; Calder Hall was the first."},
{"id": "bwr", "name": "Boiling water reactor", "year": 1957, "cat": "energy", "wiki": "Boiling water reactor", "req": ["pwr"], "desc": "A light-water reactor that boils its coolant directly to drive the turbine."},
{"id": "gas_centrifuge", "name": "Gas centrifuge", "year": 1957, "cat": "energy", "wiki": "Gas centrifuge", "req": ["enriched_uranium"], "desc": "Spinning uranium hexafluoride to separate isotopes, far more energy-efficient than gaseous diffusion."},
{"id": "sodium_fast_reactor", "name": "Sodium-cooled fast reactor", "year": 1959, "cat": "energy", "wiki": "Sodium-cooled fast reactor", "req": ["breeder_reactor"], "desc": "A fast-neutron reactor cooled by liquid sodium, the main breeder design."},
{"id": "candu", "name": "CANDU reactor", "year": 1962, "cat": "energy", "wiki": "CANDU reactor", "req": ["nuclear_reactor", "heavy_water"], "desc": "A Canadian heavy-water reactor that runs on natural uranium and refuels on line."},
{"id": "mox_fuel", "name": "MOX fuel", "year": 1963, "cat": "energy", "wiki": "MOX fuel", "req": ["nuclear_reprocessing"], "desc": "Reactor fuel blending plutonium and uranium oxides, recycling separated plutonium."},
{"id": "molten_salt_reactor", "name": "Molten-salt reactor", "year": 1965, "cat": "energy", "wiki": "Molten-salt reactor", "req": ["nuclear_reactor"], "desc": "A reactor with fuel dissolved in molten fluoride salt, demonstrated by Oak Ridge's MSRE."},
{"id": "pebble_bed_reactor", "name": "Pebble-bed reactor", "year": 1966, "cat": "energy", "wiki": "Pebble-bed reactor", "req": ["nuclear_reactor"], "desc": "A helium-cooled reactor fuelled by graphite pebbles, high-temperature and passively safe."},
{"id": "lead_cooled_fast_reactor", "name": "Lead-cooled fast reactor", "year": 1971, "cat": "energy", "wiki": "Lead-cooled fast reactor", "req": ["breeder_reactor"], "desc": "A fast reactor cooled by molten lead or lead-bismuth, first used in Soviet Alfa-class submarines."},
{"id": "rbmk", "name": "RBMK", "year": 1973, "cat": "energy", "wiki": "RBMK", "req": ["nuclear_reactor"], "desc": "A Soviet graphite-moderated, water-cooled channel reactor, the type that failed at Chernobyl."},
{"id": "agr", "name": "Advanced gas-cooled reactor", "year": 1976, "cat": "energy", "wiki": "Advanced gas-cooled reactor", "req": ["magnox", "enriched_uranium"], "desc": "The second-generation British reactor with CO2 coolant and enriched oxide fuel."},
{"id": "dry_cask_storage", "name": "Dry cask storage", "year": 1986, "cat": "energy", "wiki": "Dry cask storage", "req": ["nuclear_power_plant"], "desc": "Storing cooled spent fuel in sealed steel and concrete casks on site."},
{"id": "generation_iii_reactor", "name": "Generation III reactor", "year": 1996, "cat": "energy", "wiki": "Generation III reactor", "req": ["pwr", "bwr"], "desc": "Evolved light-water designs with improved fuel, passive safety and longer life."},
{"id": "deep_geological_repository", "name": "Deep geological repository", "year": 1999, "cat": "energy", "wiki": "Deep geological repository", "req": ["nuclear_reprocessing"], "desc": "Mined storage deep in stable rock for long-lived radioactive waste."},
{"id": "small_modular_reactor", "name": "Small modular reactor", "year": 2020, "cat": "energy", "wiki": "Small modular reactor", "req": ["generation_iii_reactor"], "desc": "A factory-built reactor of under about 300 MW, first operating afloat in Russia in 2020."},
{"id": "z_pinch", "name": "Z-pinch", "year": 1946, "cat": "energy", "wiki": "Z-pinch", "req": ["quantum_mechanics", "electromagnetism"], "desc": "Confining plasma by the magnetic field of a strong axial current, one of the first fusion concepts."},
{"id": "magnetic_confinement_fusion", "name": "Magnetic confinement fusion", "year": 1951, "cat": "energy", "wiki": "Magnetic confinement fusion", "req": ["quantum_mechanics", "electromagnet"], "desc": "Holding hot fusion plasma in magnetic fields, the main path pursued toward fusion power."},
{"id": "stellarator", "name": "Stellarator", "year": 1953, "cat": "energy", "wiki": "Stellarator", "req": ["magnetic_confinement_fusion"], "desc": "Spitzer's fusion device confining plasma with externally twisted magnetic coils."},
{"id": "tokamak", "name": "Tokamak", "year": 1958, "cat": "energy", "wiki": "Tokamak", "req": ["magnetic_confinement_fusion"], "desc": "A Soviet toroidal fusion device with a plasma current, the leading magnetic confinement design."},
{"id": "fusor", "name": "Fusor", "year": 1964, "cat": "energy", "wiki": "Fusor", "req": ["vacuum_pump", "quantum_mechanics"], "desc": "Farnsworth's inertial electrostatic confinement device, a simple neutron source that achieves fusion."},
{"id": "inertial_confinement_fusion", "name": "Inertial confinement fusion", "year": 1972, "cat": "energy", "wiki": "Inertial confinement fusion", "req": ["laser", "nuclear_weapon"], "desc": "Compressing fuel pellets with lasers or particle beams until they fuse before flying apart."},
{"id": "jet_tokamak", "name": "Joint European Torus", "year": 1983, "cat": "energy", "wiki": "Joint European Torus", "req": ["tokamak"], "desc": "The largest tokamak of its era, which set fusion energy records with deuterium-tritium fuel."},
{"id": "spherical_tokamak", "name": "Spherical tokamak", "year": 1991, "cat": "energy", "wiki": "Spherical tokamak", "req": ["tokamak"], "desc": "A compact, low-aspect-ratio tokamak, demonstrated by START at Culham."},
{"id": "wendelstein_7x", "name": "Wendelstein 7-X", "year": 2015, "cat": "energy", "wiki": "Wendelstein 7-X", "req": ["stellarator", "electronic_computer", "superconducting_magnet", "niobium_titanium"], "desc": "A computer-optimised superconducting stellarator in Germany testing steady-state confinement."},
{"id": "nif_ignition", "name": "NIF fusion ignition", "year": 2022, "cat": "energy", "wiki": "National Ignition Facility", "req": ["inertial_confinement_fusion", "laser"], "desc": "In December 2022 NIF's laser-driven implosion released more fusion energy than the laser energy delivered."},
{"id": "wind_turbine", "name": "Wind turbine", "year": 1887, "cat": "energy", "wiki": "Wind turbine", "req": ["windmill", "dynamo"], "desc": "A wind-driven electricity generator, first built by James Blyth and Charles Brush."},
{"id": "vertical_axis_wind_turbine", "name": "Vertical-axis wind turbine", "year": 1922, "cat": "energy", "wiki": "Vertical-axis wind turbine", "req": ["wind_turbine", "panemone_windmill"], "desc": "Wind turbines whose rotor shaft is vertical, accepting wind from any direction."},
{"id": "savonius_turbine", "name": "Savonius wind turbine", "year": 1922, "cat": "energy", "wiki": "Savonius wind turbine", "req": ["vertical_axis_wind_turbine"], "desc": "A simple drag-type vertical-axis turbine made of curved scoops."},
{"id": "darrieus_turbine", "name": "Darrieus wind turbine", "year": 1931, "cat": "energy", "wiki": "Darrieus wind turbine", "req": ["vertical_axis_wind_turbine"], "desc": "A lift-type vertical-axis wind turbine with curved blades."},
{"id": "smith_putnam", "name": "Smith–Putnam wind turbine", "year": 1941, "cat": "energy", "wiki": "Smith–Putnam wind turbine", "req": ["wind_turbine", "alternator"], "desc": "The first megawatt-scale wind turbine, synchronised to a utility grid in Vermont."},
{"id": "wind_farm", "name": "Wind farm", "year": 1980, "cat": "energy", "wiki": "Wind farm", "req": ["wind_turbine", "electrical_grid"], "desc": "Arrays of utility-scale turbines feeding the grid, begun in California's wind rush."},
{"id": "offshore_wind", "name": "Offshore wind power", "year": 1991, "cat": "energy", "wiki": "Offshore wind power", "req": ["wind_farm"], "desc": "Wind farms at sea, first at Vindeby in Denmark, using stronger and steadier winds."},
{"id": "floating_offshore_wind", "name": "Floating offshore wind", "year": 2009, "cat": "energy", "wiki": "Floating offshore wind", "req": ["offshore_wind", "oil_platform"], "desc": "Turbines on moored floating platforms for waters too deep for fixed foundations."},
{"id": "solar_cooker", "name": "Solar cooker", "year": 1767, "cat": "energy", "wiki": "Solar cooker", "req": ["glass"], "desc": "A glazed hot box or reflector concentrating sunlight to cook food, first built by de Saussure."},
{"id": "photovoltaic_effect", "name": "Photovoltaic effect", "year": 1839, "cat": "energy", "wiki": "Photovoltaic effect", "req": ["voltaic_pile"], "desc": "Becquerel's discovery that light falling on certain materials generates a voltage."},
{"id": "solar_water_heating", "name": "Solar water heating", "year": 1891, "cat": "energy", "wiki": "Solar water heating", "req": ["glass"], "desc": "Collectors that heat water with sunlight, sold commercially from the 1890s."},
{"id": "parabolic_trough", "name": "Parabolic trough", "year": 1912, "cat": "energy", "wiki": "Parabolic trough", "req": ["solar_cooker", "steam_engine"], "desc": "Curved mirrors focusing sunlight on a pipe; Shuman's 1912 Egyptian plant pumped irrigation water."},
{"id": "concentrated_solar_power", "name": "Concentrated solar power", "year": 1968, "cat": "energy", "wiki": "Concentrated solar power", "req": ["parabolic_trough", "steam_turbine"], "desc": "Generating electricity by concentrating sunlight to drive a heat engine, with thermal storage for night."},
{"id": "solar_furnace", "name": "Solar furnace", "year": 1970, "cat": "energy", "wiki": "Solar furnace", "req": ["parabolic_trough"], "desc": "A field of mirrors concentrating sunlight to over 3000 C, as at Odeillo in France."},
{"id": "solar_tracker", "name": "Solar tracker", "year": 1970, "cat": "energy", "wiki": "Solar tracker", "req": ["solar_cell", "electric_motor"], "desc": "A mount that turns panels or mirrors to follow the sun, raising energy yield."},
{"id": "thin_film_solar_cell", "name": "Thin-film solar cell", "year": 1976, "cat": "energy", "wiki": "Thin-film solar cell", "req": ["solar_cell", "amorphous_silicon"], "desc": "Cells made of micron-thin layers such as amorphous silicon, using far less material."},
{"id": "cigs_solar_cell", "name": "CIGS solar cell", "year": 1976, "cat": "energy", "wiki": "Copper indium gallium selenide solar cell", "req": ["thin_film_solar_cell"], "desc": "A thin-film cell using copper indium gallium selenide, flexible and efficient."},
{"id": "concentrator_photovoltaics", "name": "Concentrator photovoltaics", "year": 1976, "cat": "energy", "wiki": "Concentrator photovoltaics", "req": ["solar_cell", "parabolic_trough"], "desc": "Using lenses or mirrors to focus sunlight onto small high-efficiency cells."},
{"id": "solar_inverter", "name": "Solar inverter", "year": 1980, "cat": "energy", "wiki": "Solar inverter", "req": ["solar_cell", "transistor"], "desc": "Converts DC from solar panels to grid AC and tracks the panels' maximum power point."},
{"id": "solar_power_tower", "name": "Solar power tower", "year": 1981, "cat": "energy", "wiki": "Solar power tower", "req": ["concentrated_solar_power"], "desc": "Heliostats focusing sunlight on a central receiver tower, often storing heat in molten salt."},
{"id": "cdte_photovoltaics", "name": "Cadmium telluride photovoltaics", "year": 1981, "cat": "energy", "wiki": "Cadmium telluride photovoltaics", "req": ["thin_film_solar_cell"], "desc": "The cheapest thin-film technology, mass-produced from the 2000s."},
{"id": "solar_updraft_tower", "name": "Solar updraft tower", "year": 1982, "cat": "energy", "wiki": "Solar updraft tower", "req": ["solar_water_heating", "wind_turbine"], "desc": "A large greenhouse and chimney driving air through turbines, demonstrated at Manzanares in Spain."},
{"id": "photovoltaic_power_station", "name": "Photovoltaic power station", "year": 1982, "cat": "energy", "wiki": "Photovoltaic power station", "req": ["solar_cell", "electrical_grid"], "desc": "Utility-scale solar farms feeding the grid, now the fastest-growing source of electricity."},
{"id": "multi_junction_solar_cell", "name": "Multi-junction solar cell", "year": 1983, "cat": "energy", "wiki": "Multi-junction solar cell", "req": ["solar_cell", "gallium_arsenide", "mocvd"], "desc": "Stacked cells of different band gaps reaching the highest efficiencies, used on spacecraft."},
{"id": "thermal_energy_storage", "name": "Thermal energy storage", "year": 1985, "cat": "energy", "wiki": "Thermal energy storage", "req": ["concentrated_solar_power"], "desc": "Storing heat or cold, for example in molten salt at solar plants, for later use."},
{"id": "organic_solar_cell", "name": "Organic solar cell", "year": 1986, "cat": "energy", "wiki": "Organic solar cell", "req": ["thin_film_solar_cell", "conductive_polymer"], "desc": "Cells built from carbon-based semiconductors, potentially cheap and flexible."},
{"id": "heterojunction_solar_cell", "name": "Heterojunction solar cell", "year": 1990, "cat": "energy", "wiki": "Heterojunction solar cell", "req": ["solar_cell", "thin_film_solar_cell", "amorphous_silicon"], "desc": "Crystalline silicon wafers coated with amorphous silicon layers for high efficiency."},
{"id": "dye_sensitized_solar_cell", "name": "Dye-sensitized solar cell", "year": 1991, "cat": "energy", "wiki": "Dye-sensitized solar cell", "req": ["thin_film_solar_cell", "titanium_dioxide"], "desc": "The Graetzel cell, using a dye on titanium dioxide to mimic photosynthesis."},
{"id": "agrivoltaics", "name": "Agrivoltaics", "year": 2004, "cat": "energy", "wiki": "Agrivoltaics", "req": ["photovoltaic_power_station"], "desc": "Sharing land between solar panels and crops or grazing."},
{"id": "quantum_dot_solar_cell", "name": "Quantum dot solar cell", "year": 2005, "cat": "energy", "wiki": "Quantum dot solar cell", "req": ["thin_film_solar_cell"], "desc": "Cells using semiconductor nanocrystals whose band gap is tuned by size."},
{"id": "floating_solar", "name": "Floating solar", "year": 2007, "cat": "energy", "wiki": "Floating solar", "req": ["photovoltaic_power_station"], "desc": "Solar arrays mounted on pontoons on reservoirs and lakes."},
{"id": "perovskite_solar_cell", "name": "Perovskite solar cell", "year": 2009, "cat": "energy", "wiki": "Perovskite solar cell", "req": ["dye_sensitized_solar_cell", "solar_cell", "perovskite_oxides"], "desc": "Cells using perovskite-structured absorbers whose efficiency rose faster than any prior PV material."},
{"id": "geothermal_heating", "name": "Geothermal heating", "year": 1332, "cat": "energy", "wiki": "Geothermal heating", "req": ["irrigation"], "desc": "Using hot springs and ground heat directly to warm buildings, as at Chaudes-Aigues from the 14th century."},
{"id": "geothermal_power", "name": "Geothermal power", "year": 1904, "cat": "energy", "wiki": "Geothermal power", "req": ["steam_turbine", "electric_generator"], "desc": "Generating electricity from underground steam or hot water, first at Larderello, Italy."},
{"id": "binary_cycle", "name": "Binary cycle power", "year": 1967, "cat": "energy", "wiki": "Binary cycle", "req": ["geothermal_power", "organic_rankine_cycle"], "desc": "Using moderate-temperature geothermal water to boil a secondary fluid that drives the turbine."},
{"id": "enhanced_geothermal_system", "name": "Enhanced geothermal system", "year": 1977, "cat": "energy", "wiki": "Enhanced geothermal system", "req": ["geothermal_power", "fracking"], "desc": "Creating heat reservoirs in hot dry rock by hydraulic stimulation, trialled at Fenton Hill."},
{"id": "tidal_power", "name": "Tidal power", "year": 1966, "cat": "energy", "wiki": "Tidal power", "req": ["tide_mill"], "desc": "Electricity from tidal range or currents; the Rance barrage in France opened in 1966."},
{"id": "tidal_stream_generator", "name": "Tidal stream generator", "year": 2003, "cat": "energy", "wiki": "Tidal stream generator", "req": ["tidal_power", "wind_turbine"], "desc": "Underwater rotors driven by tidal currents, like wind turbines in water."},
{"id": "wave_power", "name": "Wave power", "year": 1965, "cat": "energy", "wiki": "Wave power", "req": ["water_turbine"], "desc": "Capturing ocean wave energy, first in Masuda's oscillating-water-column navigation buoys."},
{"id": "otec", "name": "Ocean thermal energy conversion", "year": 1930, "cat": "energy", "wiki": "Ocean thermal energy conversion", "req": ["steam_turbine", "thermodynamics"], "desc": "Running a heat engine on the temperature difference between warm surface and cold deep seawater."},
{"id": "osmotic_power", "name": "Osmotic power", "year": 2009, "cat": "energy", "wiki": "Osmotic power", "req": ["hydroelectricity", "modern_chemistry"], "desc": "Generating power from the salinity difference between fresh and seawater, prototyped in Norway."},
{"id": "biogas", "name": "Biogas", "year": 1859, "cat": "energy", "wiki": "Biogas", "req": ["coal_gas"], "desc": "Methane-rich gas from anaerobic digestion of organic waste, used for cooking, heat and power."},
{"id": "waste_to_energy", "name": "Waste-to-energy", "year": 1874, "cat": "energy", "wiki": "Waste-to-energy", "req": ["fire_tube_boiler"], "desc": "Burning municipal waste to produce steam and electricity, from Victorian refuse destructors onward."},
{"id": "ethanol_fuel", "name": "Ethanol fuel", "year": 1876, "cat": "energy", "wiki": "Ethanol fuel", "req": ["distillation", "four_stroke_engine"], "desc": "Alcohol from crops burned as motor fuel, mass-adopted in Brazil from 1975."},
{"id": "wood_gas_generator", "name": "Wood gas generator", "year": 1901, "cat": "energy", "wiki": "Wood gas generator", "req": ["coal_gas", "internal_combustion_engine"], "desc": "A gasifier turning wood or charcoal into fuel gas to run engines, common in wartime fuel shortages."},
{"id": "biodiesel", "name": "Biodiesel", "year": 1937, "cat": "energy", "wiki": "Biodiesel", "req": ["diesel_engine"], "desc": "Diesel fuel made by transesterifying vegetable oils or animal fats."},
{"id": "sustainable_aviation_fuel", "name": "Sustainable aviation fuel", "year": 2008, "cat": "energy", "wiki": "Aviation biofuel", "req": ["biodiesel", "fischer_tropsch"], "desc": "Jet fuel from biomass, waste oils or synthesis, cutting lifecycle aviation emissions."},
{"id": "thermoelectric_effect", "name": "Thermoelectric effect", "year": 1821, "cat": "energy", "wiki": "Thermoelectric effect", "req": ["electromagnetism"], "desc": "Seebeck's discovery that a temperature difference across joined metals produces a voltage."},
{"id": "daniell_cell", "name": "Daniell cell", "year": 1836, "cat": "energy", "wiki": "Daniell cell", "req": ["voltaic_pile"], "desc": "A two-electrolyte copper-zinc cell giving steady current, which powered early telegraphs."},
{"id": "lead_acid_battery", "name": "Lead–acid battery", "year": 1859, "cat": "energy", "wiki": "Lead–acid battery", "req": ["daniell_cell"], "desc": "Planté's rechargeable battery, still standard for car starting and backup power."},
{"id": "leclanche_cell", "name": "Leclanché cell", "year": 1866, "cat": "energy", "wiki": "Leclanché cell", "req": ["daniell_cell"], "desc": "A zinc and manganese dioxide cell with ammonium chloride electrolyte, ancestor of the dry cell."},
{"id": "zinc_carbon_battery", "name": "Zinc–carbon battery", "year": 1886, "cat": "energy", "wiki": "Zinc–carbon battery", "req": ["leclanche_cell"], "desc": "Gassner's sealed dry cell, the first mass-market portable battery."},
{"id": "nickel_cadmium_battery", "name": "Nickel–cadmium battery", "year": 1899, "cat": "energy", "wiki": "Nickel–cadmium battery", "req": ["lead_acid_battery"], "desc": "Jungner's rugged rechargeable alkaline battery, later sealed for portable devices."},
{"id": "nickel_iron_battery", "name": "Nickel–iron battery", "year": 1901, "cat": "energy", "wiki": "Nickel–iron battery", "req": ["nickel_cadmium_battery"], "desc": "Edison's very durable alkaline storage battery for vehicles and railways."},
{"id": "zinc_air_battery", "name": "Zinc–air battery", "year": 1932, "cat": "energy", "wiki": "Zinc–air battery", "req": ["leclanche_cell"], "desc": "A battery oxidising zinc with oxygen from the air, very energy-dense, used in hearing aids."},
{"id": "mercury_battery", "name": "Mercury battery", "year": 1942, "cat": "energy", "wiki": "Mercury battery", "req": ["zinc_carbon_battery"], "desc": "Ruben's zinc-mercuric oxide cell with steady voltage, later banned for its mercury."},
{"id": "alkaline_battery", "name": "Alkaline battery", "year": 1959, "cat": "energy", "wiki": "Alkaline battery", "req": ["zinc_carbon_battery", "mercury_battery"], "desc": "Urry's zinc-manganese dioxide cell with alkaline electrolyte, longer-lasting than zinc-carbon."},
{"id": "silver_oxide_battery", "name": "Silver oxide battery", "year": 1960, "cat": "energy", "wiki": "Silver oxide battery", "req": ["mercury_battery"], "desc": "A high-energy primary button cell for watches and calculators."},
{"id": "lithium_battery", "name": "Lithium primary battery", "year": 1970, "cat": "energy", "wiki": "Lithium battery", "req": ["alkaline_battery", "modern_chemistry"], "desc": "Non-rechargeable cells with lithium anodes, offering high energy density and long shelf life."},
{"id": "nickel_hydrogen_battery", "name": "Nickel–hydrogen battery", "year": 1975, "cat": "energy", "wiki": "Nickel–hydrogen battery", "req": ["nickel_cadmium_battery"], "desc": "A long-lived rechargeable battery with a pressurised hydrogen electrode, used on satellites and Hubble."},
{"id": "lithium_cobalt_oxide", "name": "Lithium cobalt oxide cathode", "year": 1980, "cat": "energy", "wiki": "Lithium cobalt oxide", "req": ["lithium_battery"], "desc": "Goodenough's layered intercalation cathode that made the lithium-ion battery practical."},
{"id": "nimh_battery", "name": "Nickel–metal hydride battery", "year": 1989, "cat": "energy", "wiki": "Nickel–metal hydride battery", "req": ["nickel_cadmium_battery"], "desc": "A rechargeable battery with a hydrogen-absorbing alloy anode, used in early hybrid cars."},
{"id": "solid_state_battery", "name": "Solid-state battery", "year": 1992, "cat": "energy", "wiki": "Solid-state battery", "req": ["lithium_ion_battery"], "desc": "A battery with a solid electrolyte, from thin-film LiPON cells toward safer, denser EV batteries."},
{"id": "lfp_battery", "name": "Lithium iron phosphate battery", "year": 1996, "cat": "energy", "wiki": "Lithium iron phosphate battery", "req": ["lithium_ion_battery"], "desc": "A cobalt-free lithium-ion chemistry that is safer and longer-lived, now common in EVs and storage."},
{"id": "lmo_battery", "name": "Lithium manganese oxide battery", "year": 1996, "cat": "energy", "wiki": "Lithium ion manganese oxide battery", "req": ["lithium_ion_battery"], "desc": "A lithium-ion chemistry with a spinel manganese cathode, cheap and thermally stable."},
{"id": "lithium_polymer_battery", "name": "Lithium polymer battery", "year": 1997, "cat": "energy", "wiki": "Lithium polymer battery", "req": ["lithium_ion_battery"], "desc": "A lithium-ion battery with a polymer or gel electrolyte in a flexible pouch."},
{"id": "nca_battery", "name": "NCA cathode", "year": 1999, "cat": "energy", "wiki": "Lithium nickel cobalt aluminium oxides", "req": ["lithium_cobalt_oxide", "lithium_ion_battery"], "desc": "Nickel-cobalt-aluminium cathodes with very high energy density, used in Tesla cars."},
{"id": "nmc_battery", "name": "NMC cathode", "year": 2001, "cat": "energy", "wiki": "Lithium nickel manganese cobalt oxides", "req": ["lithium_cobalt_oxide", "lithium_ion_battery"], "desc": "Nickel-manganese-cobalt layered cathodes giving the high energy density of most EV batteries."},
{"id": "lithium_titanate_battery", "name": "Lithium-titanate battery", "year": 2008, "cat": "energy", "wiki": "Lithium-titanate battery", "req": ["lithium_ion_battery"], "desc": "A lithium-ion battery with a titanate anode allowing very fast charging and long cycle life."},
{"id": "lithium_sulfur_battery", "name": "Lithium–sulfur battery", "year": 2010, "cat": "energy", "wiki": "Lithium–sulfur battery", "req": ["lithium_ion_battery"], "desc": "A light, high-energy battery with a sulfur cathode, used in high-altitude drones."},
{"id": "sodium_ion_battery", "name": "Sodium-ion battery", "year": 2023, "cat": "energy", "wiki": "Sodium-ion battery", "req": ["lithium_ion_battery"], "desc": "A lithium-ion analogue using abundant sodium, reaching mass-produced cars in 2023."},
{"id": "sodium_sulfur_battery", "name": "Sodium–sulfur battery", "year": 1967, "cat": "energy", "wiki": "Sodium–sulfur battery", "req": ["lead_acid_battery", "modern_chemistry"], "desc": "A molten-salt battery with a ceramic electrolyte, used for grid storage."},
{"id": "flow_battery", "name": "Flow battery", "year": 1974, "cat": "energy", "wiki": "Flow battery", "req": ["lead_acid_battery"], "desc": "A rechargeable battery storing energy in liquid electrolytes in external tanks, scalable for the grid."},
{"id": "zinc_bromine_battery", "name": "Zinc–bromine battery", "year": 1977, "cat": "energy", "wiki": "Zinc–bromine battery", "req": ["flow_battery"], "desc": "A hybrid flow battery plating zinc from a bromide electrolyte, for stationary storage."},
{"id": "vanadium_redox_battery", "name": "Vanadium redox battery", "year": 1986, "cat": "energy", "wiki": "Vanadium redox battery", "req": ["flow_battery"], "desc": "A flow battery using vanadium in both electrolytes, avoiding cross-contamination."},
{"id": "flywheel_energy_storage", "name": "Flywheel energy storage", "year": 1950, "cat": "energy", "wiki": "Flywheel energy storage", "req": ["electric_motor", "steel"], "desc": "Storing energy in a spinning rotor, first in the Swiss gyrobus and now for grid frequency control."},
{"id": "compressed_air_energy_storage", "name": "Compressed-air energy storage", "year": 1978, "cat": "energy", "wiki": "Compressed-air energy storage", "req": ["gas_turbine"], "desc": "Storing energy as compressed air in caverns, first at Huntorf in Germany."},
{"id": "liquid_air_storage", "name": "Liquid air energy storage", "year": 2011, "cat": "energy", "wiki": "Cryogenic energy storage", "req": ["lng", "compressed_air_energy_storage", "liquefaction_of_gases"], "desc": "Storing energy by liquefying air and later expanding it through a turbine."},
{"id": "battery_energy_storage", "name": "Battery energy storage system", "year": 1986, "cat": "energy", "wiki": "Battery energy storage system", "req": ["lead_acid_battery", "electrical_grid"], "desc": "Grid-connected battery banks for balancing and backup, scaled up with lithium-ion from the 2010s."},
{"id": "hornsdale_power_reserve", "name": "Hornsdale Power Reserve", "year": 2017, "cat": "energy", "wiki": "Hornsdale Power Reserve", "req": ["battery_energy_storage", "lithium_ion_battery", "wind_farm"], "desc": "A 100 MW lithium-ion grid battery in South Australia that showed batteries could stabilise a grid."},
{"id": "electrolysis_of_water", "name": "Electrolysis of water", "year": 1800, "cat": "energy", "wiki": "Electrolysis of water", "req": ["electrolysis", "voltaic_pile"], "desc": "Splitting water into hydrogen and oxygen with electric current, now central to green hydrogen."},
{"id": "fuel_cell", "name": "Fuel cell", "year": 1839, "cat": "energy", "wiki": "Fuel cell", "req": ["electrolysis_of_water"], "desc": "Grove's gas battery converting hydrogen and oxygen directly into electricity."},
{"id": "solid_oxide_fuel_cell", "name": "Solid oxide fuel cell", "year": 1937, "cat": "energy", "wiki": "Solid oxide fuel cell", "req": ["fuel_cell"], "desc": "A high-temperature fuel cell with a ceramic electrolyte that can run on hydrocarbons."},
{"id": "alkaline_fuel_cell", "name": "Alkaline fuel cell", "year": 1959, "cat": "energy", "wiki": "Alkaline fuel cell", "req": ["fuel_cell"], "desc": "Bacon's practical hydrogen-oxygen cell, which powered the Apollo spacecraft."},
{"id": "molten_carbonate_fuel_cell", "name": "Molten carbonate fuel cell", "year": 1960, "cat": "energy", "wiki": "Molten carbonate fuel cell", "req": ["fuel_cell"], "desc": "A high-temperature fuel cell with a molten carbonate electrolyte, for stationary power."},
{"id": "hydrogen_storage", "name": "Hydrogen storage", "year": 1960, "cat": "energy", "wiki": "Hydrogen storage", "req": ["electrolysis_of_water", "liquid_rocket", "liquefaction_of_gases"], "desc": "Compressed, liquefied or material-based methods of storing hydrogen fuel."},
{"id": "pem_fuel_cell", "name": "Proton-exchange membrane fuel cell", "year": 1962, "cat": "energy", "wiki": "Proton-exchange membrane fuel cell", "req": ["fuel_cell"], "desc": "A low-temperature fuel cell with a polymer membrane, used on Gemini and in fuel-cell cars."},
{"id": "pem_electrolysis", "name": "PEM electrolysis", "year": 1966, "cat": "energy", "wiki": "Proton exchange membrane electrolysis", "req": ["electrolysis_of_water", "pem_fuel_cell"], "desc": "Splitting water across a solid polymer membrane, suited to variable renewable power."},
{"id": "hydrogen_economy", "name": "Hydrogen economy", "year": 1970, "cat": "energy", "wiki": "Hydrogen economy", "req": ["fuel_cell", "electrolysis_of_water", "steam_reforming"], "desc": "A proposed energy system using hydrogen as the main carrier for transport, industry and storage."},
{"id": "phosphoric_acid_fuel_cell", "name": "Phosphoric acid fuel cell", "year": 1975, "cat": "energy", "wiki": "Phosphoric acid fuel cell", "req": ["fuel_cell"], "desc": "The first commercially sold fuel cell type, used for building power and heat."},
{"id": "solid_oxide_electrolyzer", "name": "Solid oxide electrolyzer cell", "year": 1980, "cat": "energy", "wiki": "Solid oxide electrolyzer cell", "req": ["solid_oxide_fuel_cell", "electrolysis_of_water"], "desc": "A fuel cell run in reverse at high temperature to split steam efficiently."},
{"id": "direct_methanol_fuel_cell", "name": "Direct methanol fuel cell", "year": 1990, "cat": "energy", "wiki": "Direct methanol fuel cell", "req": ["pem_fuel_cell"], "desc": "A PEM fuel cell oxidising liquid methanol directly, for portable power."},
{"id": "power_to_gas", "name": "Power-to-gas", "year": 2013, "cat": "energy", "wiki": "Power-to-gas", "req": ["pem_electrolysis", "natural_gas"], "desc": "Converting surplus electricity into hydrogen or synthetic methane for storage in gas networks."},
{"id": "carbon_capture", "name": "Carbon capture and storage", "year": 1972, "cat": "energy", "wiki": "Carbon capture and storage", "req": ["amine_gas_treating", "enhanced_oil_recovery"], "desc": "Capturing CO2 from industry or power plants and storing it underground."},
{"id": "beccs", "name": "Bioenergy with carbon capture", "year": 2011, "cat": "energy", "wiki": "Bioenergy with carbon capture and storage", "req": ["carbon_capture", "ethanol_fuel"], "desc": "Capturing CO2 from biomass energy plants for storage, a route to negative emissions."},
{"id": "direct_air_capture", "name": "Direct air capture", "year": 2017, "cat": "energy", "wiki": "Direct air capture", "req": ["carbon_capture"], "desc": "Extracting CO2 directly from ambient air with sorbents, first commercially in Switzerland."},
{"id": "oldowan", "name": "Oldowan industry", "year": -2600000, "cat": "foundations", "wiki": "Oldowan", "req": ["stone_tools"], "desc": "The earliest stone tool tradition: simple choppers and sharp flakes struck from river cobbles."},
{"id": "bone_tool", "name": "Bone tools", "year": -1500000, "cat": "foundations", "wiki": "Bone tool", "req": ["stone_tools"], "desc": "Implements shaped from bone and antler, later used for awls, needles, points and harpoons."},
{"id": "hand_axe", "name": "Hand axe", "year": -1760000, "cat": "foundations", "wiki": "Hand axe", "req": ["oldowan", "stone_tools"], "desc": "The bifacially flaked Acheulean tool, used across Africa and Eurasia for over a million years."},
{"id": "cooking", "name": "Cooking", "year": -500000, "cat": "foundations", "wiki": "Cooking", "req": ["control_of_fire"], "desc": "Heating food to make it safer and more digestible, which reshaped human diet and anatomy."},
{"id": "levallois", "name": "Levallois technique", "year": -300000, "cat": "foundations", "wiki": "Levallois technique", "req": ["hand_axe"], "desc": "A prepared-core method that let knappers plan and strike flakes of predetermined shape."},
{"id": "hafting", "name": "Hafting", "year": -300000, "cat": "foundations", "wiki": "Hafting", "req": ["levallois", "stone_tools"], "desc": "Attaching stone points or blades to wooden handles or shafts to make composite tools."},
{"id": "birch_tar", "name": "Birch tar", "year": -200000, "cat": "foundations", "wiki": "Birch bark tar", "req": ["control_of_fire", "hafting", "stone_tools"], "desc": "An adhesive distilled from birch bark by heating, the oldest known synthetic material."},
{"id": "bead", "name": "Beads", "year": -100000, "cat": "daily", "wiki": "Bead", "req": ["stone_tools"], "desc": "Perforated shells and stones strung as ornaments, early evidence of symbolic culture."},
{"id": "pressure_flaking", "name": "Pressure flaking", "year": -75000, "cat": "foundations", "wiki": "Lithic reduction", "req": ["levallois", "bone_tool"], "desc": "Removing fine flakes by pressing with a bone or antler tool, giving sharp, precise edges."},
{"id": "raft", "name": "Raft", "year": -50000, "cat": "foundations", "wiki": "Raft", "req": ["cordage"], "desc": "Logs or reeds lashed into a floating platform, likely used in the settlement of Australia."},
{"id": "burin", "name": "Burin", "year": -40000, "cat": "foundations", "wiki": "Burin (lithic flake)", "req": ["pressure_flaking"], "desc": "A chisel-edged flint tool for engraving and working bone, antler and wood."},
{"id": "blade_technology", "name": "Lithic blades", "year": -40000, "cat": "foundations", "wiki": "Lithic blade", "req": ["levallois"], "desc": "Long, parallel-sided flakes struck from prepared cores, typical of the Upper Paleolithic."},
{"id": "tent", "name": "Tent", "year": -40000, "cat": "daily", "wiki": "Tent", "req": ["cordage", "clothing"], "desc": "A portable shelter of hides or fabric stretched over poles."},
{"id": "shoe", "name": "Footwear", "year": -40000, "cat": "daily", "wiki": "Shoe", "req": ["clothing", "sewing_needle"], "desc": "Protective coverings for the feet, from hide wraps to sewn shoes and sandals."},
{"id": "ground_stone", "name": "Ground stone tools", "year": -40000, "cat": "foundations", "wiki": "Ground stone", "req": ["stone_tools"], "desc": "Tools shaped by grinding and polishing rather than flaking, such as querns and polished axes."},
{"id": "mortar_and_pestle", "name": "Mortar and pestle", "year": -35000, "cat": "foundations", "wiki": "Mortar and pestle", "req": ["ground_stone"], "desc": "A bowl and club for crushing seeds, pigments and medicines."},
{"id": "microlith", "name": "Microliths", "year": -35000, "cat": "foundations", "wiki": "Microlith", "req": ["blade_technology", "hafting"], "desc": "Tiny standardized stone blades set in rows into handles and arrows."},
{"id": "stone_boiling", "name": "Stone boiling", "year": -30000, "cat": "foundations", "wiki": "Stone boiling", "req": ["cooking"], "desc": "Heating water in skin, bark or basket containers by dropping in hot stones."},
{"id": "earth_oven", "name": "Earth oven", "year": -29000, "cat": "foundations", "wiki": "Earth oven", "req": ["cooking"], "desc": "A pit lined with heated stones for slow-cooking food, one of the oldest cooking structures."},
{"id": "net", "name": "Net", "year": -27000, "cat": "foundations", "wiki": "Net (device)", "req": ["cordage"], "desc": "A mesh of knotted cord used to catch fish, birds and small game."},
{"id": "fish_hook", "name": "Fish hook", "year": -23000, "cat": "foundations", "wiki": "Fish hook", "req": ["bone_tool"], "desc": "A bent or barbed point of shell, bone and later metal for catching fish."},
{"id": "oil_lamp", "name": "Oil lamp", "year": -15000, "cat": "foundations", "wiki": "Oil lamp", "req": ["control_of_fire"], "desc": "A hollowed stone or clay vessel burning fat or oil through a wick for portable light."},
{"id": "basket", "name": "Basket weaving", "year": -10000, "cat": "foundations", "wiki": "Basket weaving", "req": ["cordage"], "desc": "Interlacing plant fibers into containers, mats and traps."},
{"id": "ladder", "name": "Ladder", "year": -10000, "cat": "foundations", "wiki": "Ladder", "req": ["cordage"], "desc": "A frame of rungs for climbing, depicted in Mesolithic rock art."},
{"id": "water_well", "name": "Water well", "year": -8000, "cat": "daily", "wiki": "Well", "req": ["agriculture"], "desc": "A shaft dug to reach groundwater, allowing settlement away from rivers."},
{"id": "adze", "name": "Adze", "year": -8000, "cat": "foundations", "wiki": "Adze", "req": ["ground_stone", "hafting"], "desc": "A hafted cutting tool with a transverse blade for shaping timber."},
{"id": "bow_drill", "name": "Bow drill", "year": -7000, "cat": "foundations", "wiki": "Bow drill", "req": ["bow_and_arrow", "cordage"], "desc": "A bowstring wrapped around a spindle to spin it fast, used to drill beads and to make fire."},
{"id": "fire_striker", "name": "Fire striker", "year": -3300, "cat": "foundations", "wiki": "Fire striker", "req": ["stone_tools"], "desc": "Striking flint against pyrite or later steel to throw sparks onto tinder."},
{"id": "candle", "name": "Candle", "year": -500, "cat": "daily", "wiki": "Candle", "req": ["oil_lamp"], "desc": "A wick embedded in solid tallow or wax, a cheap and portable source of light."},
{"id": "mirror", "name": "Mirror", "year": -6000, "cat": "daily", "wiki": "Mirror", "req": ["ground_stone"], "desc": "A reflecting surface, first of polished obsidian, later of bronze and silvered glass."},
{"id": "comb", "name": "Comb", "year": -5000, "cat": "daily", "wiki": "Comb", "req": ["bone_tool"], "desc": "A toothed tool of bone, wood or shell for grooming hair."},
{"id": "cosmetics", "name": "Cosmetics", "year": -4000, "cat": "daily", "wiki": "Cosmetics", "req": ["mortar_and_pestle"], "desc": "Ground minerals and pigments such as kohl and ochre applied to the body."},
{"id": "board_game", "name": "Board games", "year": -3500, "cat": "daily", "wiki": "Board game", "req": ["stone_tools"], "desc": "Games with pieces on a marked surface, such as Senet and the Royal Game of Ur."},
{"id": "dice", "name": "Dice", "year": -3000, "cat": "daily", "wiki": "Dice", "req": ["bone_tool"], "desc": "Marked cubes of bone or stone used as random number generators in games."},
{"id": "soap", "name": "Soap", "year": -2800, "cat": "daily", "wiki": "Soap", "req": ["pottery", "control_of_fire"], "desc": "Fats boiled with alkaline ash, recorded in Babylon, used for washing and textiles."},
{"id": "indus_sanitation", "name": "Indus Valley sanitation", "year": -2600, "cat": "daily", "wiki": "Sanitation of the Indus Valley Civilisation", "req": ["mudbrick", "pottery", "fired_brick"], "desc": "Covered brick drains, bathrooms and toilets serving whole cities like Mohenjo-daro."},
{"id": "plumbing", "name": "Plumbing", "year": -2400, "cat": "daily", "wiki": "Plumbing", "req": ["smelting", "pottery"], "desc": "Pipes of clay, copper and lead that carry water into buildings and waste out of them."},
{"id": "lock", "name": "Lock and key", "year": -2000, "cat": "daily", "wiki": "Lock and key", "req": ["lever"], "desc": "A mechanism that secures a door or box, from Egyptian wooden pin locks to metal locks."},
{"id": "button", "name": "Button", "year": -2000, "cat": "daily", "wiki": "Button", "req": ["bead"], "desc": "A small disc used first as ornament, then from the 13th century as a garment fastener."},
{"id": "scissors", "name": "Scissors", "year": -1500, "cat": "daily", "wiki": "Scissors", "req": ["bronze"], "desc": "Paired blades for cutting, first as spring shears and later pivoted."},
{"id": "fibula", "name": "Fibula brooch", "year": -1300, "cat": "daily", "wiki": "Fibula (brooch)", "req": ["bronze"], "desc": "A spring-pin clothing fastener of the Bronze and Iron Ages, ancestor of the safety pin."},
{"id": "chopsticks", "name": "Chopsticks", "year": -1200, "cat": "daily", "wiki": "Chopsticks", "req": ["cooking"], "desc": "Paired sticks for cooking and eating, widespread in East Asia."},
{"id": "perfume", "name": "Perfume", "year": -1200, "cat": "daily", "wiki": "Perfume", "req": ["cosmetics"], "desc": "Aromatic oils extracted from plants and resins, recorded by the Mesopotamian chemist Tapputi."},
{"id": "cloaca_maxima", "name": "Cloaca Maxima", "year": -600, "cat": "daily", "wiki": "Cloaca Maxima", "req": ["lime_mortar", "indus_sanitation"], "desc": "Rome's great covered sewer, among the earliest large municipal drainage systems."},
{"id": "umbrella", "name": "Umbrella", "year": -400, "cat": "daily", "wiki": "Umbrella", "req": ["weaving"], "desc": "A canopy on a pole for shade or rain; collapsible versions appeared in ancient China."},
{"id": "yakhchal", "name": "Yakhchal", "year": -400, "cat": "daily", "wiki": "Yakhchāl", "req": ["mudbrick", "qanat", "lime_mortar"], "desc": "A Persian domed ice house that stored ice through desert summers."},
{"id": "clothes_iron", "name": "Clothes iron", "year": -100, "cat": "daily", "wiki": "Clothes iron", "req": ["bronze"], "desc": "A heated metal tool for pressing cloth, first a pan of hot coals in Han China."},
{"id": "toilet_paper", "name": "Toilet paper", "year": 589, "cat": "daily", "wiki": "Toilet paper", "req": ["paper"], "desc": "Paper for personal hygiene, first recorded in 6th-century China."},
{"id": "playing_cards", "name": "Playing cards", "year": 868, "cat": "daily", "wiki": "Playing card", "req": ["paper"], "desc": "Printed card decks for games, spreading from Tang China to Europe."},
{"id": "toothbrush", "name": "Toothbrush", "year": 1498, "cat": "daily", "wiki": "Toothbrush", "req": ["domestication_of_animals"], "desc": "A handle with animal bristles for cleaning teeth, recorded in Ming China."},
{"id": "flush_toilet", "name": "Flush toilet", "year": 1596, "cat": "daily", "wiki": "Flush toilet", "req": ["plumbing"], "desc": "A toilet that washes waste away with water, designed by John Harington."},
{"id": "pressure_cooker", "name": "Pressure cooking", "year": 1679, "cat": "daily", "wiki": "Pressure cooker", "req": ["cooking", "vacuum_pump", "steam_digester"], "desc": "Cooking in a sealed vessel above water's normal boiling point, pioneered by Denis Papin."},
{"id": "kitchen_stove", "name": "Kitchen stove", "year": 1735, "cat": "daily", "wiki": "Kitchen stove", "req": ["cast_iron", "chimney"], "desc": "An enclosed firebox with cooking holes, replacing open-hearth cooking."},
{"id": "franklin_stove", "name": "Franklin stove", "year": 1742, "cat": "daily", "wiki": "Franklin stove", "req": ["cast_iron", "chimney"], "desc": "Benjamin Franklin's metal-lined fireplace that radiated more heat into the room."},
{"id": "shower", "name": "Shower", "year": 1767, "cat": "daily", "wiki": "Shower", "req": ["plumbing"], "desc": "A hand-pumped overhead spray for bathing, patented by William Feetham."},
{"id": "trap_plumbing", "name": "Plumbing trap", "year": 1775, "cat": "daily", "wiki": "Trap (plumbing)", "req": ["flush_toilet"], "desc": "Alexander Cumming's S-bend, a water seal that blocks sewer gas from entering homes."},
{"id": "lever_tumbler_lock", "name": "Lever tumbler lock", "year": 1778, "cat": "daily", "wiki": "Lever tumbler lock", "req": ["lock"], "desc": "A lock with multiple levers that must all be lifted correctly, much harder to pick."},
{"id": "argand_lamp", "name": "Argand lamp", "year": 1780, "cat": "daily", "wiki": "Argand lamp", "req": ["oil_lamp", "glass"], "desc": "An oil lamp with a hollow wick and glass chimney that burned far brighter and cleaner."},
{"id": "gas_lighting", "name": "Gas lighting", "year": 1792, "cat": "daily", "wiki": "Gas lighting", "req": ["coal_mining", "distillation", "coal_gas"], "desc": "Lighting with coal gas piped to burners, which lit factories and city streets."},
{"id": "bleach", "name": "Bleach", "year": 1799, "cat": "daily", "wiki": "Bleach", "req": ["modern_chemistry"], "desc": "Chlorine compounds for whitening cloth and disinfecting, made cheaply as bleaching powder."},
{"id": "fire_extinguisher", "name": "Fire extinguisher", "year": 1818, "cat": "daily", "wiki": "Fire extinguisher", "req": ["modern_chemistry"], "desc": "A portable pressurized container of water or chemicals for putting out fires."},
{"id": "dobereiner_lamp", "name": "Döbereiner's lamp", "year": 1823, "cat": "daily", "wiki": "Döbereiner's lamp", "req": ["modern_chemistry"], "desc": "A hydrogen lighter ignited by a platinum catalyst, the first commercial lighter."},
{"id": "friction_match", "name": "Friction match", "year": 1826, "cat": "daily", "wiki": "Match", "req": ["modern_chemistry"], "desc": "A stick tipped with chemicals that ignites when struck, invented by John Walker."},
{"id": "gas_stove", "name": "Gas stove", "year": 1826, "cat": "daily", "wiki": "Gas stove", "req": ["kitchen_stove", "gas_lighting"], "desc": "A cooking stove fueled by piped gas, giving instant, controllable heat."},
{"id": "lawn_mower", "name": "Lawn mower", "year": 1830, "cat": "daily", "wiki": "Lawn mower", "req": ["cast_iron", "gear"], "desc": "Edwin Budding's reel mower, which made close-cut lawns practical."},
{"id": "silvered_mirror", "name": "Silvered glass mirror", "year": 1835, "cat": "daily", "wiki": "Silvering", "req": ["mirror", "glass", "modern_chemistry"], "desc": "Justus von Liebig's chemical deposition of silver on glass, making cheap clear mirrors."},
{"id": "sanitary_sewer", "name": "Sanitary sewer", "year": 1843, "cat": "daily", "wiki": "Sanitary sewer", "req": ["plumbing", "cast_iron"], "desc": "Underground pipe networks that carry household sewage away from cities."},
{"id": "pin_tumbler_lock", "name": "Pin tumbler lock", "year": 1848, "cat": "daily", "wiki": "Pin tumbler lock", "req": ["lock", "machine_tools"], "desc": "The Yale cylinder lock with spring pins, still the most common door lock."},
{"id": "safety_pin", "name": "Safety pin", "year": 1849, "cat": "daily", "wiki": "Safety pin", "req": ["fibula", "steel"], "desc": "Walter Hunt's bent wire pin with a clasp that shields the point."},
{"id": "washing_machine", "name": "Washing machine", "year": 1851, "cat": "daily", "wiki": "Washing machine", "req": ["cast_iron", "gear"], "desc": "A machine that agitates clothes in water; electric models followed in 1908."},
{"id": "kerosene_lamp", "name": "Kerosene lamp", "year": 1853, "cat": "daily", "wiki": "Kerosene lamp", "req": ["argand_lamp", "distillation", "kerosene"], "desc": "A wick lamp burning refined kerosene, the main domestic light before electricity."},
{"id": "security_alarm", "name": "Burglar alarm", "year": 1853, "cat": "daily", "wiki": "Security alarm", "req": ["electromagnet", "telegraph"], "desc": "An electric circuit that rings a bell when a door or window is opened."},
{"id": "can_opener", "name": "Can opener", "year": 1855, "cat": "daily", "wiki": "Can opener", "req": ["canning", "steel"], "desc": "A hand tool for cutting open sealed tin cans."},
{"id": "septic_tank", "name": "Septic tank", "year": 1860, "cat": "daily", "wiki": "Septic tank", "req": ["sanitary_sewer"], "desc": "An underground tank where sewage settles and decomposes, for homes off the sewer network."},
{"id": "london_sewer", "name": "London sewerage system", "year": 1865, "cat": "daily", "wiki": "London sewer system", "req": ["sanitary_sewer", "portland_cement"], "desc": "Joseph Bazalgette's intercepting sewers, which ended London's cholera epidemics."},
{"id": "water_heater", "name": "Water heater", "year": 1868, "cat": "daily", "wiki": "Water heating", "req": ["plumbing", "gas_lighting"], "desc": "A gas-fired appliance that supplies hot water on demand to a home."},
{"id": "carpet_sweeper", "name": "Carpet sweeper", "year": 1876, "cat": "daily", "wiki": "Carpet sweeper", "req": ["gear"], "desc": "A push device with rotating brushes that lifts dirt from carpets."},
{"id": "cash_register", "name": "Cash register", "year": 1879, "cat": "daily", "wiki": "Cash register", "req": ["gear", "coinage"], "desc": "James Ritty's mechanical till that recorded sales and deterred theft."},
{"id": "safety_razor", "name": "Safety razor", "year": 1880, "cat": "daily", "wiki": "Safety razor", "req": ["steel"], "desc": "A razor with a guard over the blade; disposable blades followed in 1901."},
{"id": "ceiling_fan", "name": "Electric fan", "year": 1882, "cat": "daily", "wiki": "Ceiling fan", "req": ["electric_motor"], "desc": "A motor-driven fan that cools rooms by moving air."},
{"id": "vending_machine", "name": "Vending machine", "year": 1883, "cat": "daily", "wiki": "Vending machine", "req": ["coinage", "machine_tools"], "desc": "A coin-operated machine that dispenses goods without a clerk."},
{"id": "thermostat", "name": "Thermostat", "year": 1883, "cat": "daily", "wiki": "Thermostat", "req": ["central_heating", "electromagnet"], "desc": "A device that switches heating on and off to hold a set temperature."},
{"id": "gas_mantle", "name": "Gas mantle", "year": 1885, "cat": "daily", "wiki": "Gas mantle", "req": ["gas_lighting"], "desc": "Welsbach's mesh of rare-earth oxides that glows white-hot, greatly brightening gas lamps."},
{"id": "snap_fastener", "name": "Snap fastener", "year": 1885, "cat": "daily", "wiki": "Snap fastener", "req": ["machine_tools"], "desc": "A pair of interlocking metal discs that press together to fasten clothing."},
{"id": "dishwasher", "name": "Dishwasher", "year": 1886, "cat": "daily", "wiki": "Dishwasher", "req": ["plumbing", "gear"], "desc": "Josephine Cochrane's machine that sprayed hot water onto racked dishes."},
{"id": "electric_kettle", "name": "Electric kettle", "year": 1891, "cat": "daily", "wiki": "Kettle", "req": ["electrical_grid"], "desc": "A kettle with an internal electric heating element for boiling water."},
{"id": "vacuum_flask", "name": "Vacuum flask", "year": 1892, "cat": "daily", "wiki": "Vacuum flask", "req": ["vacuum_pump", "glass", "liquefaction_of_gases"], "desc": "James Dewar's double-walled evacuated vessel that keeps liquids hot or cold."},
{"id": "electric_stove", "name": "Electric stove", "year": 1892, "cat": "daily", "wiki": "Electric stove", "req": ["kitchen_stove", "electrical_grid"], "desc": "A cooking range heated by electric resistance elements."},
{"id": "toaster", "name": "Toaster", "year": 1893, "cat": "daily", "wiki": "Toaster", "req": ["electrical_grid"], "desc": "An electric appliance that browns bread with glowing heating wires."},
{"id": "flashlight", "name": "Flashlight", "year": 1899, "cat": "daily", "wiki": "Flashlight", "req": ["voltaic_pile", "light_bulb"], "desc": "A portable battery-powered electric light."},
{"id": "paper_clip", "name": "Paper clip", "year": 1899, "cat": "daily", "wiki": "Paper clip", "req": ["steel", "machine_tools"], "desc": "A bent steel wire that holds sheets of paper together."},
{"id": "vacuum_cleaner", "name": "Vacuum cleaner", "year": 1901, "cat": "daily", "wiki": "Vacuum cleaner", "req": ["electric_motor", "vacuum_pump"], "desc": "A machine that sucks dust from floors; Hubert Booth's version began powered cleaning."},
{"id": "power_plug", "name": "Plugs and sockets", "year": 1904, "cat": "daily", "wiki": "AC power plugs and sockets", "req": ["electrical_grid"], "desc": "Detachable connectors that let appliances draw mains electricity from wall outlets."},
{"id": "aluminium_foil", "name": "Aluminium foil", "year": 1910, "cat": "daily", "wiki": "Aluminium foil", "req": ["aluminium_smelting", "rolling_mill"], "desc": "Thin rolled aluminium sheet for wrapping and preserving food."},
{"id": "refrigerator", "name": "Refrigerator", "year": 1913, "cat": "daily", "wiki": "Refrigerator", "req": ["refrigeration", "electric_motor", "icebox"], "desc": "The electric household refrigerator, which transformed food storage and diet."},
{"id": "zipper", "name": "Zipper", "year": 1913, "cat": "daily", "wiki": "Zipper", "req": ["interchangeable_parts"], "desc": "Gideon Sundback's interlocking-tooth slide fastener for clothing and bags."},
{"id": "clothes_dryer", "name": "Clothes dryer", "year": 1915, "cat": "daily", "wiki": "Clothes dryer", "req": ["electric_motor", "washing_machine"], "desc": "A heated tumbling drum that dries laundry indoors."},
{"id": "detergent", "name": "Synthetic detergent", "year": 1916, "cat": "daily", "wiki": "Detergent", "req": ["soap", "modern_chemistry"], "desc": "Synthetic surfactants that clean in hard water where soap forms scum."},
{"id": "blender", "name": "Blender", "year": 1922, "cat": "daily", "wiki": "Blender (appliance)", "req": ["electric_motor"], "desc": "A motorized jar with spinning blades for mixing and pureeing food."},
{"id": "garbage_disposal", "name": "Garbage disposal unit", "year": 1927, "cat": "daily", "wiki": "Garbage disposal unit", "req": ["electric_motor", "sanitary_sewer"], "desc": "A sink-mounted grinder that shreds food waste into the sewer."},
{"id": "electric_razor", "name": "Electric razor", "year": 1928, "cat": "daily", "wiki": "Electric shaver", "req": ["electric_motor", "safety_razor"], "desc": "Jacob Schick's motor-driven dry shaver."},
{"id": "microwave_oven", "name": "Microwave oven", "year": 1947, "cat": "daily", "wiki": "Microwave oven", "req": ["radar", "cavity_magnetron"], "desc": "An oven that heats food with microwaves from a magnetron, found by radar engineer Percy Spencer."},
{"id": "rice_cooker", "name": "Electric rice cooker", "year": 1955, "cat": "daily", "wiki": "Rice cooker", "req": ["electrical_grid", "thermostat"], "desc": "An automatic cooker that switches off when rice is done, transforming Asian kitchens."},
{"id": "hook_and_loop", "name": "Hook-and-loop fastener", "year": 1955, "cat": "daily", "wiki": "Velcro", "req": ["weaving", "modern_chemistry", "nylon"], "desc": "George de Mestral's Velcro, two nylon strips of hooks and loops that grip each other."},
{"id": "residual_current_device", "name": "Residual-current device", "year": 1955, "cat": "daily", "wiki": "Residual-current device", "req": ["transformer", "electrical_grid"], "desc": "A safety switch that cuts power when current leaks to earth, preventing electrocution."},
{"id": "smoke_detector", "name": "Smoke detector", "year": 1965, "cat": "daily", "wiki": "Smoke detector", "req": ["radioactivity", "transistor"], "desc": "A battery-powered ionization alarm that warns of fire in the home."},
{"id": "induction_cooking", "name": "Induction cooking", "year": 1973, "cat": "daily", "wiki": "Induction cooking", "req": ["transistor", "electromagnetism"], "desc": "Heating pans directly by electromagnetic induction from a coil under the hob."},
{"id": "keycard_lock", "name": "Keycard lock", "year": 1975, "cat": "daily", "wiki": "Keycard lock", "req": ["lock", "magnetic_stripe_card"], "desc": "A lock opened by a coded card, now standard in hotels and offices."},
{"id": "robotic_vacuum", "name": "Robotic vacuum cleaner", "year": 2002, "cat": "daily", "wiki": "Robotic vacuum cleaner", "req": ["vacuum_cleaner", "microprocessor"], "desc": "An autonomous floor-cleaning robot that navigates a home with sensors."},
{"id": "smart_thermostat", "name": "Smart thermostat", "year": 2011, "cat": "daily", "wiki": "Smart thermostat", "req": ["thermostat", "internet"], "desc": "A networked, learning thermostat that schedules heating and can be controlled remotely."},
{"id": "smart_speaker", "name": "Smart speaker", "year": 2014, "cat": "daily", "wiki": "Smart speaker", "req": ["internet", "artificial_intelligence", "virtual_assistant"], "desc": "A voice-controlled speaker with a built-in assistant that also runs home automation."},
{"id": "banking", "name": "Banking", "year": -2000, "cat": "knowledge", "wiki": "History of banking", "req": ["writing", "numerals"], "desc": "Lending and deposit-taking, from Mesopotamian temples to Italian banking houses."},
{"id": "banknote", "name": "Banknote", "year": 1024, "cat": "knowledge", "wiki": "Banknote", "req": ["paper", "coinage"], "desc": "Government-issued paper money, first the Jiaozi of Song China."},
{"id": "double_entry", "name": "Double-entry bookkeeping", "year": 1300, "cat": "knowledge", "wiki": "Double-entry bookkeeping", "req": ["hindu_arabic_numerals", "banking"], "desc": "Recording every transaction as matching debit and credit, the basis of modern accounting."},
{"id": "marine_insurance", "name": "Marine insurance", "year": 1347, "cat": "knowledge", "wiki": "Marine insurance", "req": ["banking"], "desc": "Contracts that spread the risk of losing ships and cargo, the first modern insurance."},
{"id": "patent", "name": "Patent", "year": 1474, "cat": "knowledge", "wiki": "Patent", "req": ["writing"], "desc": "A temporary legal monopoly granted to inventors, starting with the Venetian statute of 1474."},
{"id": "joint_stock_company", "name": "Joint-stock company", "year": 1602, "cat": "knowledge", "wiki": "Joint-stock company", "req": ["banking", "double_entry"], "desc": "A firm owned by tradable shares, pioneered by the Dutch East India Company."},
{"id": "stock_exchange", "name": "Stock exchange", "year": 1602, "cat": "knowledge", "wiki": "Stock exchange", "req": ["joint_stock_company"], "desc": "A market for trading company shares, beginning in Amsterdam."},
{"id": "central_bank", "name": "Central bank", "year": 1668, "cat": "knowledge", "wiki": "Central bank", "req": ["banking", "banknote"], "desc": "A state institution managing currency and credit, starting with Sweden's Riksbank."},
{"id": "wire_transfer", "name": "Wire transfer", "year": 1872, "cat": "daily", "wiki": "Wire transfer", "req": ["telegraph", "banking"], "desc": "Sending money by telegraph message between bank offices."},
{"id": "credit_card", "name": "Credit card", "year": 1950, "cat": "daily", "wiki": "Credit card", "req": ["banking"], "desc": "A card granting revolving credit at many merchants, beginning with Diners Club."},
{"id": "barcode", "name": "Barcode", "year": 1952, "cat": "daily", "wiki": "Barcode", "req": ["light_bulb", "punched_card"], "desc": "Machine-readable patterns of bars encoding data, patented by Woodland and Silver."},
{"id": "magnetic_stripe_card", "name": "Magnetic stripe card", "year": 1960, "cat": "daily", "wiki": "Digital card", "req": ["credit_card", "electromagnetism", "magnetic_tape"], "desc": "A plastic card with a magnetic data strip, developed at IBM."},
{"id": "atm", "name": "Automated teller machine", "year": 1967, "cat": "daily", "wiki": "ATM", "req": ["banking", "transistor"], "desc": "A machine that dispenses cash without a teller, first installed by Barclays in London."},
{"id": "upc", "name": "Universal Product Code", "year": 1974, "cat": "daily", "wiki": "Universal Product Code", "req": ["barcode", "laser", "integrated_circuit"], "desc": "The retail barcode standard, first scanned at a supermarket checkout in 1974."},
{"id": "smart_card", "name": "Smart card", "year": 1977, "cat": "daily", "wiki": "Smart card", "req": ["integrated_circuit", "credit_card"], "desc": "A plastic card with an embedded chip, used for payment, phones and identity."},
{"id": "qr_code", "name": "QR code", "year": 1994, "cat": "daily", "wiki": "QR code", "req": ["barcode"], "desc": "A two-dimensional matrix barcode developed by Denso Wave, later used for mobile payments."},
{"id": "contactless_payment", "name": "Contactless payment", "year": 1997, "cat": "daily", "wiki": "Contactless payment", "req": ["smart_card", "radio"], "desc": "Paying by tapping a card or device against a reader using short-range radio."},
{"id": "mpesa", "name": "M-Pesa", "year": 2007, "cat": "daily", "wiki": "M-Pesa", "req": ["mobile_phone", "banking"], "desc": "A phone-based money transfer service in Kenya that brought banking to millions."},
{"id": "units_of_measurement", "name": "Units of measurement", "year": -3000, "cat": "knowledge", "wiki": "Unit of measurement", "req": ["numerals", "balance_scale"], "desc": "Standardized lengths, weights and volumes such as the cubit, needed for trade and building."},
{"id": "sexagesimal", "name": "Sexagesimal system", "year": -3000, "cat": "knowledge", "wiki": "Sexagesimal", "req": ["numerals"], "desc": "Babylonian base-60 counting, still used for time and angles."},
{"id": "pythagorean_theorem", "name": "Pythagorean theorem", "year": -1800, "cat": "knowledge", "wiki": "Pythagorean theorem", "req": ["sexagesimal"], "desc": "The relation between the sides of a right triangle, known in Babylon and later proven by the Greeks."},
{"id": "method_of_exhaustion", "name": "Method of exhaustion", "year": -370, "cat": "knowledge", "wiki": "Method of exhaustion", "req": ["pythagorean_theorem"], "desc": "Finding areas and volumes by inscribing ever finer polygons, a forerunner of integration."},
{"id": "syllogism", "name": "Syllogistic logic", "year": -350, "cat": "knowledge", "wiki": "Syllogism", "req": ["writing"], "desc": "Aristotle's formal system of deductive argument, the start of logic as a discipline."},
{"id": "archimedes_principle", "name": "Archimedes' principle", "year": -250, "cat": "knowledge", "wiki": "Archimedes' principle", "req": ["geometry", "balance_scale"], "desc": "The buoyant force on a body equals the weight of fluid it displaces."},
{"id": "earth_circumference", "name": "Measuring Earth's circumference", "year": -240, "cat": "knowledge", "wiki": "Earth's circumference", "req": ["geometry", "gnomon"], "desc": "Eratosthenes' estimate of Earth's size from shadow angles at two cities."},
{"id": "negative_numbers", "name": "Negative numbers", "year": -200, "cat": "knowledge", "wiki": "Negative number", "req": ["numerals"], "desc": "Numbers below zero, used for debts in Han China and later in India."},
{"id": "trigonometry", "name": "Trigonometry", "year": -150, "cat": "knowledge", "wiki": "Trigonometry", "req": ["geometry"], "desc": "Hipparchus' tables of chords relating angles and lengths, essential to astronomy and surveying."},
{"id": "almagest", "name": "Almagest", "year": 150, "cat": "knowledge", "wiki": "Almagest", "req": ["trigonometry", "armillary_sphere"], "desc": "Ptolemy's mathematical model of planetary motion, the standard astronomy text for 1,400 years."},
{"id": "ptolemy_geography", "name": "Ptolemy's Geography", "year": 150, "cat": "knowledge", "wiki": "Geography (Ptolemy)", "req": ["trigonometry", "cartography"], "desc": "A world atlas using latitude and longitude coordinates and map projections."},
{"id": "sine_cosine", "name": "Sine function", "year": 499, "cat": "knowledge", "wiki": "Sine and cosine", "req": ["trigonometry"], "desc": "Aryabhata's half-chord tables, the trigonometric functions used ever since."},
{"id": "zero", "name": "Zero", "year": 628, "cat": "knowledge", "wiki": "0", "req": ["hindu_arabic_numerals"], "desc": "Brahmagupta's treatment of zero as a number with rules of arithmetic."},
{"id": "book_of_optics", "name": "Book of Optics", "year": 1021, "cat": "knowledge", "wiki": "Book of Optics", "req": ["geometry", "camera_obscura"], "desc": "Ibn al-Haytham's experimental study of light and vision."},
{"id": "complex_number", "name": "Complex numbers", "year": 1545, "cat": "knowledge", "wiki": "Complex number", "req": ["algebra", "negative_numbers"], "desc": "Numbers with an imaginary part, introduced by Cardano and later vital to physics and engineering."},
{"id": "analytic_geometry", "name": "Analytic geometry", "year": 1637, "cat": "knowledge", "wiki": "Analytic geometry", "req": ["algebra", "geometry"], "desc": "Descartes' coordinates that describe curves with equations."},
{"id": "probability_theory", "name": "Probability theory", "year": 1654, "cat": "knowledge", "wiki": "Probability theory", "req": ["algebra"], "desc": "The mathematics of chance, founded in Pascal and Fermat's letters on gambling."},
{"id": "statistics", "name": "Statistics", "year": 1662, "cat": "knowledge", "wiki": "Statistics", "req": ["probability_theory"], "desc": "Collecting and analyzing numerical data, begun with John Graunt's mortality tables."},
{"id": "differential_equation", "name": "Differential equations", "year": 1676, "cat": "knowledge", "wiki": "Differential equation", "req": ["calculus"], "desc": "Equations relating quantities to their rates of change, used to model physical systems."},
{"id": "normal_distribution", "name": "Normal distribution", "year": 1733, "cat": "knowledge", "wiki": "Normal distribution", "req": ["probability_theory", "calculus"], "desc": "The bell curve, found by de Moivre, central to statistics and error analysis."},
{"id": "graph_theory", "name": "Graph theory", "year": 1736, "cat": "knowledge", "wiki": "Graph theory", "req": ["geometry"], "desc": "Euler's study of networks of nodes and edges, begun with the Königsberg bridges."},
{"id": "bayes_theorem", "name": "Bayes' theorem", "year": 1763, "cat": "knowledge", "wiki": "Bayes' theorem", "req": ["probability_theory"], "desc": "A rule for updating probabilities with new evidence."},
{"id": "modular_arithmetic", "name": "Modular arithmetic", "year": 1801, "cat": "knowledge", "wiki": "Modular arithmetic", "req": ["algebra"], "desc": "Gauss's arithmetic of remainders, later the core of public-key cryptography."},
{"id": "least_squares", "name": "Least squares", "year": 1805, "cat": "knowledge", "wiki": "Least squares", "req": ["statistics", "calculus"], "desc": "Fitting a model to data by minimizing squared errors, from Legendre and Gauss."},
{"id": "fourier_analysis", "name": "Fourier analysis", "year": 1822, "cat": "knowledge", "wiki": "Fourier analysis", "req": ["calculus", "trigonometry"], "desc": "Decomposing functions into sums of sine waves, essential to signals, sound and imaging."},
{"id": "non_euclidean_geometry", "name": "Non-Euclidean geometry", "year": 1830, "cat": "knowledge", "wiki": "Non-Euclidean geometry", "req": ["geometry"], "desc": "Consistent geometries where Euclid's parallel postulate fails, later used by general relativity."},
{"id": "group_theory", "name": "Group theory", "year": 1832, "cat": "knowledge", "wiki": "Group theory", "req": ["algebra"], "desc": "The algebra of symmetry, begun by Galois, now basic to physics and cryptography."},
{"id": "matrix", "name": "Matrix algebra", "year": 1858, "cat": "knowledge", "wiki": "Matrix (mathematics)", "req": ["algebra"], "desc": "Rectangular arrays of numbers and their algebra, formalized by Cayley."},
{"id": "control_theory", "name": "Control theory", "year": 1868, "cat": "knowledge", "wiki": "Control theory", "req": ["differential_equation", "classical_mechanics", "centrifugal_governor"], "desc": "The mathematics of feedback, started by Maxwell's analysis of governors."},
{"id": "set_theory", "name": "Set theory", "year": 1874, "cat": "knowledge", "wiki": "Set theory", "req": ["algebra"], "desc": "Cantor's theory of collections and infinities, a foundation for all of mathematics."},
{"id": "first_order_logic", "name": "First-order logic", "year": 1879, "cat": "knowledge", "wiki": "First-order logic", "req": ["boolean_algebra", "syllogism"], "desc": "Frege's formal logic with quantifiers, the basis of mathematical logic."},
{"id": "vector_calculus", "name": "Vector calculus", "year": 1881, "cat": "knowledge", "wiki": "Vector calculus", "req": ["calculus", "maxwell_equations"], "desc": "Gibbs and Heaviside's notation for fields in three dimensions."},
{"id": "regression_analysis", "name": "Regression analysis", "year": 1886, "cat": "knowledge", "wiki": "Regression analysis", "req": ["least_squares"], "desc": "Galton's method for estimating relationships between variables."},
{"id": "hypothesis_testing", "name": "Statistical hypothesis testing", "year": 1925, "cat": "knowledge", "wiki": "Statistical hypothesis test", "req": ["statistics"], "desc": "Fisher's framework for judging whether data support a claim, standard in experimental science."},
{"id": "game_theory", "name": "Game theory", "year": 1928, "cat": "knowledge", "wiki": "Game theory", "req": ["probability_theory"], "desc": "Von Neumann's mathematics of strategic decision-making."},
{"id": "incompleteness_theorems", "name": "Gödel's incompleteness theorems", "year": 1931, "cat": "knowledge", "wiki": "Gödel's incompleteness theorems", "req": ["first_order_logic", "set_theory"], "desc": "Proof that any consistent formal system of arithmetic has unprovable truths."},
{"id": "probability_axioms", "name": "Kolmogorov axioms", "year": 1933, "cat": "knowledge", "wiki": "Probability axioms", "req": ["probability_theory", "set_theory"], "desc": "The rigorous axiomatic foundation of probability theory."},
{"id": "theory_of_computation", "name": "Theory of computation", "year": 1936, "cat": "knowledge", "wiki": "Theory of computation", "req": ["incompleteness_theorems", "turing_machine"], "desc": "Turing and Church's formal definition of what can be computed by an algorithm."},
{"id": "linear_programming", "name": "Linear programming", "year": 1947, "cat": "knowledge", "wiki": "Linear programming", "req": ["matrix"], "desc": "Optimizing a linear objective under constraints; Dantzig's simplex method made it practical."},
{"id": "cybernetics", "name": "Cybernetics", "year": 1948, "cat": "knowledge", "wiki": "Cybernetics", "req": ["control_theory", "information_theory"], "desc": "Wiener's study of control and communication in machines and living things."},
{"id": "sampling_theorem", "name": "Sampling theorem", "year": 1949, "cat": "knowledge", "wiki": "Nyquist–Shannon sampling theorem", "req": ["fourier_analysis", "information_theory"], "desc": "How often a signal must be sampled to be reconstructed, the basis of digital audio and video."},
{"id": "error_correction_code", "name": "Error-correcting codes", "year": 1950, "cat": "knowledge", "wiki": "Error correction code", "req": ["information_theory"], "desc": "Hamming's codes that detect and fix transmission errors, used in memory, disks and links."},
{"id": "kalman_filter", "name": "Kalman filter", "year": 1960, "cat": "knowledge", "wiki": "Kalman filter", "req": ["control_theory", "probability_theory"], "desc": "An algorithm that estimates a system's state from noisy measurements, used in navigation."},
{"id": "chaos_theory", "name": "Chaos theory", "year": 1963, "cat": "knowledge", "wiki": "Chaos theory", "req": ["differential_equation", "electronic_computer"], "desc": "Lorenz's finding that deterministic systems can be unpredictable, limiting weather forecasts."},
{"id": "complexity_theory", "name": "Computational complexity theory", "year": 1965, "cat": "knowledge", "wiki": "Computational complexity theory", "req": ["theory_of_computation"], "desc": "Classifying problems by the time and memory needed to solve them."},
{"id": "fractal", "name": "Fractal geometry", "year": 1975, "cat": "knowledge", "wiki": "Fractal", "req": ["chaos_theory", "electronic_computer"], "desc": "Mandelbrot's geometry of self-similar shapes, used in modeling and graphics."},
{"id": "heliocentrism", "name": "Heliocentrism", "year": 1543, "cat": "knowledge", "wiki": "Copernican heliocentrism", "req": ["almagest"], "desc": "Copernicus' Sun-centered model of the solar system."},
{"id": "kepler_laws", "name": "Kepler's laws", "year": 1609, "cat": "knowledge", "wiki": "Kepler's laws of planetary motion", "req": ["heliocentrism"], "desc": "Elliptical orbits and the laws governing planetary speeds."},
{"id": "pascals_law", "name": "Pascal's law", "year": 1653, "cat": "knowledge", "wiki": "Pascal's law", "req": ["scientific_method", "barometer"], "desc": "Pressure in a confined fluid is transmitted equally, the principle of hydraulic machines."},
{"id": "boyles_law", "name": "Boyle's law", "year": 1662, "cat": "knowledge", "wiki": "Boyle's law", "req": ["vacuum_pump"], "desc": "The inverse relation between a gas's pressure and volume."},
{"id": "stratigraphy", "name": "Stratigraphy", "year": 1669, "cat": "knowledge", "wiki": "Stratigraphy", "req": ["scientific_method"], "desc": "Steno's principle that rock layers record time in sequence, the basis of geology."},
{"id": "hookes_law", "name": "Hooke's law", "year": 1676, "cat": "knowledge", "wiki": "Hooke's law", "req": ["scientific_method"], "desc": "Extension of a spring is proportional to force, the basis of elasticity and spring scales."},
{"id": "speed_of_light", "name": "Speed of light measurement", "year": 1676, "cat": "knowledge", "wiki": "Rømer's determination of the speed of light", "req": ["telescope"], "desc": "Rømer's demonstration from Jupiter's moons that light travels at a finite speed."},
{"id": "universal_gravitation", "name": "Universal gravitation", "year": 1687, "cat": "knowledge", "wiki": "Newton's law of universal gravitation", "req": ["kepler_laws", "calculus"], "desc": "Newton's inverse-square law of gravity uniting celestial and terrestrial motion."},
{"id": "bernoulli_principle", "name": "Bernoulli's principle", "year": 1738, "cat": "knowledge", "wiki": "Bernoulli's principle", "req": ["classical_mechanics", "calculus"], "desc": "Faster fluid flow means lower pressure, key to aerodynamics and hydraulics."},
{"id": "atomic_theory", "name": "Atomic theory", "year": 1808, "cat": "knowledge", "wiki": "History of atomic theory", "req": ["modern_chemistry"], "desc": "Dalton's theory that elements consist of atoms combining in fixed ratios."},
{"id": "ideal_gas_law", "name": "Ideal gas law", "year": 1834, "cat": "knowledge", "wiki": "Ideal gas law", "req": ["boyles_law"], "desc": "Clapeyron's equation linking a gas's pressure, volume and temperature."},
{"id": "doppler_effect", "name": "Doppler effect", "year": 1842, "cat": "knowledge", "wiki": "Doppler effect", "req": ["classical_mechanics"], "desc": "The change in observed frequency of a wave from a moving source, used in radar and astronomy."},
{"id": "navier_stokes", "name": "Navier-Stokes equations", "year": 1845, "cat": "knowledge", "wiki": "Navier–Stokes equations", "req": ["bernoulli_principle", "differential_equation"], "desc": "Equations describing viscous fluid flow, central to engineering and weather models."},
{"id": "conservation_of_energy", "name": "Conservation of energy", "year": 1847, "cat": "knowledge", "wiki": "Conservation of energy", "req": ["thermodynamics"], "desc": "Energy is neither created nor destroyed, only converted between forms."},
{"id": "greenhouse_effect", "name": "Greenhouse effect", "year": 1856, "cat": "knowledge", "wiki": "Greenhouse effect", "req": ["thermodynamics"], "desc": "Eunice Foote and John Tyndall showed that carbon dioxide and water vapor trap heat."},
{"id": "kinetic_theory", "name": "Kinetic theory of gases", "year": 1857, "cat": "knowledge", "wiki": "Kinetic theory of gases", "req": ["classical_mechanics", "ideal_gas_law"], "desc": "Explains gas pressure and temperature as the motion of molecules."},
{"id": "entropy", "name": "Entropy", "year": 1865, "cat": "knowledge", "wiki": "Entropy", "req": ["thermodynamics"], "desc": "Clausius' measure of disorder, which sets the limits of every heat engine."},
{"id": "periodic_table", "name": "Periodic table", "year": 1869, "cat": "knowledge", "wiki": "Periodic table", "req": ["atomic_theory", "modern_chemistry"], "desc": "Mendeleev's arrangement of elements by recurring properties, which predicted new elements."},
{"id": "statistical_mechanics", "name": "Statistical mechanics", "year": 1870, "cat": "knowledge", "wiki": "Statistical mechanics", "req": ["kinetic_theory", "probability_theory", "entropy"], "desc": "Boltzmann and Gibbs' derivation of thermodynamics from the statistics of particles."},
{"id": "electromagnetic_waves", "name": "Electromagnetic waves", "year": 1887, "cat": "knowledge", "wiki": "Electromagnetic radiation", "req": ["maxwell_equations", "induction_coil"], "desc": "Hertz's demonstration of the waves Maxwell predicted, the basis of radio."},
{"id": "radioactivity", "name": "Radioactivity", "year": 1896, "cat": "knowledge", "wiki": "Radioactive decay", "req": ["photography"], "desc": "Becquerel's discovery that some elements emit radiation spontaneously."},
{"id": "electron", "name": "Electron", "year": 1897, "cat": "knowledge", "wiki": "Electron", "req": ["cathode_ray_tube"], "desc": "J. J. Thomson's discovery of the first subatomic particle, the carrier of electric current."},
{"id": "plancks_law", "name": "Planck's law", "year": 1900, "cat": "knowledge", "wiki": "Planck's law", "req": ["thermodynamics", "maxwell_equations", "bolometer"], "desc": "Black-body radiation explained by quantized energy, the start of quantum theory."},
{"id": "special_relativity", "name": "Special relativity", "year": 1905, "cat": "knowledge", "wiki": "Special relativity", "req": ["maxwell_equations", "classical_mechanics", "michelson_interferometer"], "desc": "Einstein's theory that the speed of light is constant and time and space are relative."},
{"id": "mass_energy", "name": "Mass-energy equivalence", "year": 1905, "cat": "knowledge", "wiki": "Mass–energy equivalence", "req": ["special_relativity"], "desc": "E = mc², showing mass and energy are interchangeable, the basis of nuclear power."},
{"id": "radiometric_dating", "name": "Radiometric dating", "year": 1907, "cat": "knowledge", "wiki": "Radiometric dating", "req": ["radioactivity"], "desc": "Dating rocks by radioactive decay, which established Earth's great age."},
{"id": "atomic_nucleus", "name": "Atomic nucleus", "year": 1911, "cat": "knowledge", "wiki": "Atomic nucleus", "req": ["electron", "radioactivity"], "desc": "Rutherford's discovery that an atom's mass sits in a tiny positive core."},
{"id": "superconductivity", "name": "Superconductivity", "year": 1911, "cat": "knowledge", "wiki": "Superconductivity", "req": ["refrigeration", "liquid_helium"], "desc": "Zero electrical resistance in some materials at very low temperatures, found by Kamerlingh Onnes."},
{"id": "bohr_model", "name": "Bohr model", "year": 1913, "cat": "knowledge", "wiki": "Bohr model", "req": ["atomic_nucleus", "plancks_law", "spectroscope"], "desc": "Electrons in quantized orbits, explaining atomic spectra."},
{"id": "isotope", "name": "Isotopes", "year": 1913, "cat": "knowledge", "wiki": "Isotope", "req": ["radioactivity", "periodic_table", "mass_spectrometry"], "desc": "Soddy's finding that an element can have atoms of different mass."},
{"id": "general_relativity", "name": "General relativity", "year": 1915, "cat": "knowledge", "wiki": "General relativity", "req": ["special_relativity", "universal_gravitation", "non_euclidean_geometry"], "desc": "Einstein's theory of gravity as curved spacetime, needed today for GPS accuracy."},
{"id": "chemical_bond", "name": "Chemical bond theory", "year": 1916, "cat": "knowledge", "wiki": "Chemical bond", "req": ["electron", "periodic_table"], "desc": "Lewis' electron-pair account of how atoms bond, later grounded in quantum mechanics."},
{"id": "band_theory", "name": "Electronic band theory", "year": 1928, "cat": "knowledge", "wiki": "Electronic band structure", "req": ["quantum_mechanics"], "desc": "Bloch's theory of electron energy bands in solids, which explains semiconductors."},
{"id": "neutron", "name": "Neutron", "year": 1932, "cat": "knowledge", "wiki": "Neutron", "req": ["atomic_nucleus"], "desc": "Chadwick's uncharged nuclear particle, the key to nuclear fission."},
{"id": "qed", "name": "Quantum electrodynamics", "year": 1948, "cat": "knowledge", "wiki": "Quantum electrodynamics", "req": ["quantum_mechanics", "special_relativity"], "desc": "The quantum field theory of light and matter, the most precisely tested theory in physics."},
{"id": "standard_model", "name": "Standard Model", "year": 1973, "cat": "knowledge", "wiki": "Standard Model", "req": ["qed"], "desc": "The theory of all known elementary particles and three of the four forces."},
{"id": "higgs_boson", "name": "Higgs boson discovery", "year": 2012, "cat": "knowledge", "wiki": "Higgs boson", "req": ["standard_model", "lhc"], "desc": "Confirmation at CERN's Large Hadron Collider of the particle that gives others mass."},
{"id": "gravitational_wave_detection", "name": "Gravitational wave detection", "year": 2015, "cat": "knowledge", "wiki": "First observation of gravitational waves", "req": ["general_relativity", "laser", "ligo"], "desc": "LIGO's laser interferometers detected ripples in spacetime from merging black holes."},
{"id": "linnaean_taxonomy", "name": "Linnaean taxonomy", "year": 1735, "cat": "knowledge", "wiki": "Linnaean taxonomy", "req": ["scientific_method"], "desc": "Linnaeus' hierarchical classification and two-part names for living things."},
{"id": "weather_forecasting", "name": "Weather forecasting", "year": 1861, "cat": "knowledge", "wiki": "Weather forecasting", "req": ["telegraph", "scientific_method"], "desc": "FitzRoy's storm warnings built from telegraphed observations."},
{"id": "continental_drift", "name": "Continental drift", "year": 1912, "cat": "knowledge", "wiki": "Continental drift", "req": ["cartography", "stratigraphy"], "desc": "Wegener's proposal that continents move across Earth's surface."},
{"id": "modern_synthesis", "name": "Modern evolutionary synthesis", "year": 1942, "cat": "knowledge", "wiki": "Modern synthesis (20th century)", "req": ["natural_selection", "chromosome_theory", "statistics"], "desc": "The merger of Darwinian evolution with Mendelian and population genetics."},
{"id": "radiocarbon_dating", "name": "Radiocarbon dating", "year": 1949, "cat": "knowledge", "wiki": "Radiocarbon dating", "req": ["radiometric_dating", "isotope", "geiger_counter"], "desc": "Libby's method of dating organic remains by carbon-14 decay, transforming archaeology."},
{"id": "seafloor_spreading", "name": "Seafloor spreading", "year": 1962, "cat": "knowledge", "wiki": "Seafloor spreading", "req": ["continental_drift", "echo_sounding", "magnetometer"], "desc": "Hess's finding that new ocean crust forms at mid-ocean ridges."},
{"id": "plate_tectonics", "name": "Plate tectonics", "year": 1965, "cat": "knowledge", "wiki": "Plate tectonics", "req": ["seafloor_spreading", "seismometer"], "desc": "The theory that Earth's crust moves as rigid plates, explaining earthquakes and mountains."},
{"id": "climate_model", "name": "Climate model", "year": 1967, "cat": "knowledge", "wiki": "Climate model", "req": ["greenhouse_effect", "numerical_weather_prediction"], "desc": "Manabe and Wetherald's computer model predicting warming from rising carbon dioxide."},
{"id": "cartography", "name": "Cartography", "year": -600, "cat": "knowledge", "wiki": "Cartography", "req": ["writing"], "desc": "Making maps, from the Babylonian world map to modern atlases."},
{"id": "julian_calendar", "name": "Julian calendar", "year": -45, "cat": "knowledge", "wiki": "Julian calendar", "req": ["calendar"], "desc": "Julius Caesar's 365-day solar calendar with a leap day every four years."},
{"id": "triangulation", "name": "Triangulation surveying", "year": 1533, "cat": "knowledge", "wiki": "Triangulation (surveying)", "req": ["trigonometry", "cartography", "geometry", "surveying"], "desc": "Mapping land by measuring angles in networks of triangles, described by Gemma Frisius."},
{"id": "mercator_projection", "name": "Mercator projection", "year": 1569, "cat": "knowledge", "wiki": "Mercator projection", "req": ["cartography", "trigonometry"], "desc": "A map projection that shows lines of constant compass bearing as straight lines."},
{"id": "gregorian_calendar", "name": "Gregorian calendar", "year": 1582, "cat": "knowledge", "wiki": "Gregorian calendar", "req": ["julian_calendar"], "desc": "The reformed calendar that corrected drift against the seasons, now used worldwide."},
{"id": "metric_system", "name": "Metric system", "year": 1795, "cat": "knowledge", "wiki": "Metric system", "req": ["units_of_measurement", "scientific_method", "triangulation"], "desc": "Decimal units based on natural standards, adopted by revolutionary France."},
{"id": "railway_time", "name": "Railway time", "year": 1840, "cat": "knowledge", "wiki": "Railway time", "req": ["railway", "telegraph"], "desc": "A single standard time across Britain's railways, replacing local solar time."},
{"id": "time_zone", "name": "Time zones", "year": 1883, "cat": "knowledge", "wiki": "Time zone", "req": ["railway_time"], "desc": "Dividing the world into standard time regions offset from Greenwich."},
{"id": "daylight_saving_time", "name": "Daylight saving time", "year": 1916, "cat": "knowledge", "wiki": "Daylight saving time", "req": ["time_zone"], "desc": "Shifting clocks forward in summer to extend evening daylight."},
{"id": "si_units", "name": "International System of Units", "year": 1960, "cat": "knowledge", "wiki": "International System of Units", "req": ["metric_system", "atomic_clock"], "desc": "The modern metric system of seven base units, used by science worldwide."},
{"id": "library", "name": "Library", "year": -2600, "cat": "knowledge", "wiki": "Library", "req": ["writing"], "desc": "Organized collections of written records, from Mesopotamian archives onward."},
{"id": "platonic_academy", "name": "Platonic Academy", "year": -387, "cat": "knowledge", "wiki": "Platonic Academy", "req": ["writing"], "desc": "Plato's school in Athens, a model for later institutions of learning."},
{"id": "library_of_alexandria", "name": "Library of Alexandria", "year": -285, "cat": "knowledge", "wiki": "Library of Alexandria", "req": ["library", "papyrus"], "desc": "The great Hellenistic library and research center of the ancient world."},
{"id": "encyclopedia", "name": "Encyclopedia", "year": 77, "cat": "knowledge", "wiki": "Encyclopedia", "req": ["writing", "library"], "desc": "A comprehensive reference work, from Pliny's Natural History onward."},
{"id": "house_of_wisdom", "name": "House of Wisdom", "year": 830, "cat": "knowledge", "wiki": "House of Wisdom", "req": ["library", "paper"], "desc": "Baghdad's center of translation and scholarship in the Islamic Golden Age."},
{"id": "university", "name": "University", "year": 1088, "cat": "knowledge", "wiki": "University", "req": ["library"], "desc": "Self-governing communities of scholars granting degrees, starting at Bologna."},
{"id": "royal_society", "name": "Royal Society", "year": 1660, "cat": "knowledge", "wiki": "Royal Society", "req": ["scientific_method"], "desc": "London's society for experimental science, a model for scientific academies."},
{"id": "scientific_journal", "name": "Scientific journal", "year": 1665, "cat": "knowledge", "wiki": "Academic journal", "req": ["printing_press", "royal_society"], "desc": "Periodicals that publish research results, starting with Philosophical Transactions."},
{"id": "encyclopedie", "name": "Encyclopédie", "year": 1751, "cat": "knowledge", "wiki": "Encyclopédie", "req": ["encyclopedia", "printing_press"], "desc": "Diderot and d'Alembert's Enlightenment encyclopedia, which documented crafts and technology."},
{"id": "dewey_decimal", "name": "Dewey Decimal Classification", "year": 1876, "cat": "knowledge", "wiki": "Dewey Decimal Classification", "req": ["library", "hindu_arabic_numerals"], "desc": "A numeric scheme for shelving library books by subject."},
{"id": "balance_scale", "name": "Balance scale", "year": -3000, "cat": "instruments", "wiki": "Weighing scale", "req": ["lever"], "desc": "Equal-arm beam balances in Egypt and Mesopotamia allowed goods and metals to be weighed against standard masses."},
{"id": "ruler", "name": "Ruler", "year": -2650, "cat": "instruments", "wiki": "Ruler", "req": ["numerals"], "desc": "Graduated measuring rods such as the copper-alloy Nippur cubit fixed lengths for building and trade."},
{"id": "analytical_balance", "name": "Analytical balance", "year": 1750, "cat": "instruments", "wiki": "Analytical balance", "req": ["balance_scale", "glass"], "desc": "Precision enclosed balances enabled the quantitative chemistry of Black and Lavoisier."},
{"id": "calipers", "name": "Calipers", "year": -6, "cat": "instruments", "wiki": "Calipers", "req": ["bronze", "ruler"], "desc": "Sliding bronze calipers found in a Roman-era wreck measured thicknesses and diameters."},
{"id": "vernier_scale", "name": "Vernier scale", "year": 1631, "cat": "instruments", "wiki": "Vernier scale", "req": ["ruler", "geometry"], "desc": "Pierre Vernier's auxiliary sliding scale let readings be taken to a fraction of the smallest main division."},
{"id": "micrometer_gauge", "name": "Micrometer", "year": 1640, "cat": "instruments", "wiki": "Micrometer (device)", "req": ["screw", "telescope"], "desc": "William Gascoigne's screw micrometer measured small angles in a telescope and later small lengths in workshops."},
{"id": "gnomon", "name": "Gnomon", "year": -2400, "cat": "instruments", "wiki": "Gnomon", "req": ["calendar"], "desc": "A vertical stick or pillar whose shadow tracked the sun's motion, the basis of sundials and early astronomy."},
{"id": "sundial", "name": "Sundial", "year": -1500, "cat": "instruments", "wiki": "Sundial", "req": ["gnomon"], "desc": "Egyptian shadow clocks divided daylight into hours using a gnomon's shadow on a marked surface."},
{"id": "water_clock", "name": "Water clock", "year": -1500, "cat": "instruments", "wiki": "Water clock", "req": ["pottery", "calendar"], "desc": "Vessels that measured time by a regulated flow of water, used in Egypt, Babylon and China."},
{"id": "hourglass", "name": "Hourglass", "year": 1338, "cat": "instruments", "wiki": "Hourglass", "req": ["glass"], "desc": "A sand-filled glass timer, widely used at sea from the 14th century to time watches and speed logs."},
{"id": "verge_escapement", "name": "Verge escapement", "year": 1275, "cat": "instruments", "wiki": "Verge escapement", "req": ["gear"], "desc": "The first mechanical escapement, releasing a gear train in regular steps, which made weight-driven clocks possible."},
{"id": "mainspring", "name": "Mainspring", "year": 1430, "cat": "instruments", "wiki": "Mainspring", "req": ["mechanical_clock", "steel"], "desc": "A coiled steel spring that replaced weights as a clock's power source, allowing portable timepieces."},
{"id": "pocket_watch", "name": "Pocket watch", "year": 1510, "cat": "instruments", "wiki": "Pocket watch", "req": ["mainspring", "verge_escapement"], "desc": "Spring-driven portable watches appeared in early 16th-century Germany and became common after the balance spring."},
{"id": "pendulum", "name": "Pendulum", "year": 1602, "cat": "instruments", "wiki": "Pendulum", "req": ["geometry"], "desc": "Galileo's study of the pendulum's nearly constant period gave timekeeping its first precise natural regulator."},
{"id": "pendulum_clock", "name": "Pendulum clock", "year": 1656, "cat": "instruments", "wiki": "Pendulum clock", "req": ["mechanical_clock", "pendulum"], "desc": "Christiaan Huygens' pendulum clock cut timekeeping error from minutes to seconds per day."},
{"id": "anchor_escapement", "name": "Anchor escapement", "year": 1657, "cat": "instruments", "wiki": "Anchor escapement", "req": ["pendulum_clock"], "desc": "An escapement allowing small pendulum swings, which led to the accurate longcase clock."},
{"id": "balance_spring", "name": "Balance spring", "year": 1675, "cat": "instruments", "wiki": "Balance spring", "req": ["mechanical_clock"], "desc": "A fine spiral spring regulating a watch's balance wheel, which made pocket watches accurate to minutes a day."},
{"id": "lever_escapement", "name": "Lever escapement", "year": 1755, "cat": "instruments", "wiki": "Lever escapement", "req": ["anchor_escapement", "balance_spring"], "desc": "Thomas Mudge's detached lever escapement became the standard mechanism in mechanical watches."},
{"id": "marine_chronometer", "name": "Marine chronometer", "year": 1761, "cat": "instruments", "wiki": "Marine chronometer", "req": ["balance_spring", "gridiron_pendulum", "lever_escapement"], "desc": "John Harrison's H4 kept time at sea well enough to determine longitude, transforming navigation."},
{"id": "wristwatch", "name": "Wristwatch", "year": 1868, "cat": "instruments", "wiki": "Watch", "req": ["pocket_watch", "lever_escapement"], "desc": "Watches worn on the wrist, first made by Patek Philippe and popularized by soldiers in the First World War."},
{"id": "electric_clock", "name": "Electric clock", "year": 1840, "cat": "instruments", "wiki": "Electric clock", "req": ["pendulum_clock", "electromagnet"], "desc": "Alexander Bain's clock used electromagnets to drive a pendulum, enabling synchronized networks of clocks."},
{"id": "quartz_clock", "name": "Quartz clock", "year": 1927, "cat": "instruments", "wiki": "Quartz clock", "req": ["piezoelectricity", "vacuum_tube"], "desc": "Warren Marrison and J. W. Horton's clock used a vibrating quartz crystal as a far steadier frequency reference."},
{"id": "atomic_clock", "name": "Atomic clock", "year": 1949, "cat": "instruments", "wiki": "Atomic clock", "req": ["quartz_clock", "quantum_mechanics", "radar"], "desc": "The US National Bureau of Standards built the first clock referenced to an atomic transition, using ammonia."},
{"id": "caesium_standard", "name": "Caesium atomic clock", "year": 1955, "cat": "instruments", "wiki": "Caesium standard", "req": ["atomic_clock"], "desc": "Louis Essen's caesium-beam clock at the National Physical Laboratory led to the 1967 atomic definition of the second."},
{"id": "maser", "name": "Maser", "year": 1953, "cat": "instruments", "wiki": "Maser", "req": ["quantum_mechanics", "radar"], "desc": "Charles Townes' ammonia maser amplified microwaves by stimulated emission, the forerunner of the laser."},
{"id": "hydrogen_maser", "name": "Hydrogen maser", "year": 1960, "cat": "instruments", "wiki": "Hydrogen maser", "req": ["maser", "atomic_clock"], "desc": "A maser using hydrogen atoms that gives extremely stable short-term frequency for observatories and timekeeping."},
{"id": "laser_cooling", "name": "Laser cooling", "year": 1978, "cat": "instruments", "wiki": "Laser cooling", "req": ["laser", "spectroscope"], "desc": "Techniques using laser light to slow and cool atoms to microkelvin temperatures for precision measurement."},
{"id": "frequency_comb", "name": "Optical frequency comb", "year": 2000, "cat": "instruments", "wiki": "Frequency comb", "req": ["laser", "caesium_standard"], "desc": "Mode-locked lasers producing evenly spaced frequencies let optical frequencies be counted directly against atomic clocks."},
{"id": "optical_lattice_clock", "name": "Optical lattice clock", "year": 2003, "cat": "instruments", "wiki": "Optical lattice clock", "req": ["frequency_comb", "laser_cooling"], "desc": "Clocks using atoms held in laser lattices reached accuracies of about one second in billions of years."},
{"id": "magnifying_glass", "name": "Magnifying glass", "year": 1250, "cat": "instruments", "wiki": "Magnifying glass", "req": ["lens"], "desc": "Convex lenses used as reading aids were described by Roger Bacon in the 13th century."},
{"id": "eyeglasses", "name": "Eyeglasses", "year": 1286, "cat": "instruments", "wiki": "Glasses", "req": ["lens"], "desc": "Spectacles for presbyopia appeared in Italy around 1286, extending the working lives of scholars and artisans."},
{"id": "refracting_telescope", "name": "Refracting telescope", "year": 1611, "cat": "instruments", "wiki": "Refracting telescope", "req": ["telescope"], "desc": "Kepler's convex-eyepiece design gave a wider field and became the basis of astronomical refractors."},
{"id": "reflecting_telescope", "name": "Reflecting telescope", "year": 1668, "cat": "instruments", "wiki": "Reflecting telescope", "req": ["telescope", "dispersive_prism"], "desc": "Isaac Newton's telescope used a curved mirror to avoid the colour fringing of lenses."},
{"id": "achromatic_lens", "name": "Achromatic lens", "year": 1733, "cat": "instruments", "wiki": "Achromatic lens", "req": ["refracting_telescope", "glass"], "desc": "Combining crown and flint glass elements cancelled chromatic aberration, greatly improving telescopes and microscopes."},
{"id": "spirit_level", "name": "Spirit level", "year": 1661, "cat": "instruments", "wiki": "Spirit level", "req": ["glass"], "desc": "Melchisédech Thévenot's sealed bubble vial gave a simple, precise indication of horizontal."},
{"id": "segmented_mirror", "name": "Segmented mirror telescope", "year": 1993, "cat": "instruments", "wiki": "Segmented mirror", "req": ["reflecting_telescope", "electronic_computer"], "desc": "The Keck telescope combined computer-aligned hexagonal segments into a 10-metre mirror."},
{"id": "adaptive_optics", "name": "Adaptive optics", "year": 1989, "cat": "instruments", "wiki": "Adaptive optics", "req": ["reflecting_telescope", "laser", "electronic_computer"], "desc": "Deformable mirrors correcting atmospheric turbulence in real time were first used on astronomical telescopes in 1989."},
{"id": "astrophotography", "name": "Astrophotography", "year": 1840, "cat": "instruments", "wiki": "Astrophotography", "req": ["photography", "telescope"], "desc": "John William Draper's daguerreotype of the Moon began the photographic recording of the sky."},
{"id": "fluorescence_microscope", "name": "Fluorescence microscope", "year": 1911, "cat": "instruments", "wiki": "Fluorescence microscope", "req": ["microscope"], "desc": "Microscopes imaging light emitted by fluorescent samples, later central to cell biology."},
{"id": "phase_contrast_microscopy", "name": "Phase-contrast microscopy", "year": 1932, "cat": "instruments", "wiki": "Phase-contrast microscopy", "req": ["microscope"], "desc": "Frits Zernike's method turned phase shifts into contrast, letting living unstained cells be seen."},
{"id": "confocal_microscopy", "name": "Confocal microscopy", "year": 1957, "cat": "instruments", "wiki": "Confocal microscopy", "req": ["microscope"], "desc": "Marvin Minsky's pinhole design rejected out-of-focus light, enabling optical sectioning of thick samples."},
{"id": "two_photon_microscopy", "name": "Two-photon microscopy", "year": 1990, "cat": "instruments", "wiki": "Two-photon excitation microscopy", "req": ["confocal_microscopy", "laser"], "desc": "Pulsed-laser excitation allowed deep imaging of living tissue with less damage."},
{"id": "super_resolution_microscopy", "name": "Super-resolution microscopy", "year": 2000, "cat": "instruments", "wiki": "Super-resolution microscopy", "req": ["fluorescence_microscope", "confocal_microscopy", "laser"], "desc": "Methods such as STED and PALM broke the optical diffraction limit, earning the 2014 Nobel Prize in Chemistry."},
{"id": "electron_microscope", "name": "Electron microscope", "year": 1931, "cat": "instruments", "wiki": "Electron microscope", "req": ["cathode_ray_tube", "quantum_mechanics", "vacuum_pump", "electron"], "desc": "Ernst Ruska and Max Knoll built the first electron microscope using magnetic lenses to focus electrons."},
{"id": "transmission_electron_microscopy", "name": "Transmission electron microscopy", "year": 1933, "cat": "instruments", "wiki": "Transmission electron microscopy", "req": ["electron_microscope"], "desc": "Ruska's TEM exceeded the resolution of light microscopes by passing electrons through thin specimens."},
{"id": "scanning_electron_microscope", "name": "Scanning electron microscope", "year": 1937, "cat": "instruments", "wiki": "Scanning electron microscope", "req": ["electron_microscope"], "desc": "Manfred von Ardenne's scanning design imaged surfaces with a focused beam, commercialized in 1965."},
{"id": "scanning_tunneling_microscope", "name": "Scanning tunneling microscope", "year": 1981, "cat": "instruments", "wiki": "Scanning tunneling microscope", "req": ["quantum_mechanics", "piezoelectricity", "electronic_computer"], "desc": "Binnig and Rohrer's STM imaged individual atoms on surfaces using quantum tunnelling current."},
{"id": "atomic_force_microscope", "name": "Atomic force microscope", "year": 1985, "cat": "instruments", "wiki": "Atomic force microscopy", "req": ["scanning_tunneling_microscope"], "desc": "A sharp probe on a cantilever mapped surface forces at nanometre scale, including on non-conducting samples."},
{"id": "thermoscope", "name": "Thermoscope", "year": 1593, "cat": "instruments", "wiki": "Thermoscope", "req": ["glass"], "desc": "Galileo's air thermoscope showed changes in temperature but had no fixed scale."},
{"id": "thermometer", "name": "Thermometer", "year": 1654, "cat": "instruments", "wiki": "Thermometer", "req": ["thermoscope"], "desc": "Ferdinand II of Tuscany's sealed liquid-in-glass thermometer was independent of air pressure."},
{"id": "mercury_thermometer", "name": "Mercury thermometer", "year": 1714, "cat": "instruments", "wiki": "Mercury-in-glass thermometer", "req": ["thermometer"], "desc": "Daniel Fahrenheit's mercury thermometer with a reproducible scale made temperature readings comparable."},
{"id": "pyrometer", "name": "Pyrometer", "year": 1782, "cat": "instruments", "wiki": "Pyrometer", "req": ["pottery", "thermometer"], "desc": "Josiah Wedgwood's clay-shrinkage pyrometer measured kiln temperatures beyond a thermometer's range."},
{"id": "resistance_thermometer", "name": "Resistance thermometer", "year": 1871, "cat": "instruments", "wiki": "Resistance thermometer", "req": ["galvanometer", "wheatstone_bridge"], "desc": "William Siemens' platinum resistance thermometer measured temperature from electrical resistance."},
{"id": "bolometer", "name": "Bolometer", "year": 1878, "cat": "instruments", "wiki": "Bolometer", "req": ["resistance_thermometer", "wheatstone_bridge"], "desc": "Samuel Langley's bolometer detected radiant heat, opening the infrared spectrum to measurement."},
{"id": "barometer", "name": "Barometer", "year": 1643, "cat": "instruments", "wiki": "Barometer", "req": ["glass", "scientific_method"], "desc": "Evangelista Torricelli's mercury column measured air pressure and demonstrated a vacuum."},
{"id": "hygrometer", "name": "Hygrometer", "year": 1450, "cat": "instruments", "wiki": "Hygrometer", "req": ["balance_scale"], "desc": "Nicholas of Cusa described weighing wool to gauge humidity, and later hair and dew-point hygrometers followed."},
{"id": "anemometer", "name": "Anemometer", "year": 1450, "cat": "instruments", "wiki": "Anemometer", "req": ["lever"], "desc": "Leon Battista Alberti described a swinging-plate wind gauge, later replaced by Robinson's cup anemometer."},
{"id": "rain_gauge", "name": "Rain gauge", "year": 1441, "cat": "instruments", "wiki": "Rain gauge", "req": ["ruler", "units_of_measurement"], "desc": "Standardized bronze rain gauges were distributed across Joseon Korea to record rainfall."},
{"id": "pitot_tube", "name": "Pitot tube", "year": 1732, "cat": "instruments", "wiki": "Pitot tube", "req": ["barometer"], "desc": "Henri Pitot's tube measured flow speed from pressure, later used for aircraft airspeed."},
{"id": "radiosonde", "name": "Radiosonde", "year": 1929, "cat": "instruments", "wiki": "Radiosonde", "req": ["radio", "barometer", "thermometer"], "desc": "Balloon-borne instruments radioing pressure, temperature and humidity, the backbone of upper-air forecasting."},
{"id": "weather_radar", "name": "Weather radar", "year": 1950, "cat": "instruments", "wiki": "Weather radar", "req": ["radar"], "desc": "Radar adapted to detect precipitation, giving real-time tracking of storms."},
{"id": "seismometer", "name": "Seismometer", "year": 132, "cat": "instruments", "wiki": "Seismometer", "req": ["bronze", "lever"], "desc": "Zhang Heng's bronze seismoscope indicated the direction of distant earthquakes; modern seismographs followed in the 1880s."},
{"id": "odometer", "name": "Odometer", "year": -20, "cat": "instruments", "wiki": "Odometer", "req": ["gear", "cart"], "desc": "Geared wheel counters described by Vitruvius and Heron measured distances travelled."},
{"id": "surveying", "name": "Surveying", "year": -2700, "cat": "instruments", "wiki": "Surveying", "req": ["cordage", "numerals"], "desc": "Egyptian rope stretchers measured land and laid out monuments, the origin of systematic surveying."},
{"id": "groma", "name": "Groma", "year": -300, "cat": "instruments", "wiki": "Groma (surveying)", "req": ["surveying", "geometry"], "desc": "A Roman cross-staff with plumb lines used to lay out straight roads and right-angle grids."},
{"id": "dioptra", "name": "Dioptra", "year": -200, "cat": "instruments", "wiki": "Dioptra", "req": ["surveying", "geometry"], "desc": "A Greek sighting instrument for measuring angles in surveying and astronomy."},
{"id": "theodolite", "name": "Theodolite", "year": 1576, "cat": "instruments", "wiki": "Theodolite", "req": ["dioptra", "compass", "triangulation"], "desc": "An instrument for measuring horizontal and vertical angles, central to geodetic surveying."},
{"id": "armillary_sphere", "name": "Armillary sphere", "year": -200, "cat": "instruments", "wiki": "Armillary sphere", "req": ["geometry", "calendar"], "desc": "Nested rings representing celestial circles, used to measure and demonstrate celestial positions."},
{"id": "astrolabe", "name": "Astrolabe", "year": -150, "cat": "instruments", "wiki": "Astrolabe", "req": ["armillary_sphere"], "desc": "A hand-held model of the sky used to find time, latitude and star positions, refined in the Islamic world."},
{"id": "quadrant", "name": "Quadrant", "year": 150, "cat": "instruments", "wiki": "Quadrant (instrument)", "req": ["geometry"], "desc": "A quarter-circle scale for measuring altitude angles, used in astronomy and navigation."},
{"id": "cross_staff", "name": "Jacob's staff", "year": 1342, "cat": "instruments", "wiki": "Jacob's staff", "req": ["geometry"], "desc": "Levi ben Gershon described this sliding-vane staff for measuring angles between celestial bodies."},
{"id": "mariners_astrolabe", "name": "Mariner's astrolabe", "year": 1481, "cat": "instruments", "wiki": "Mariner's astrolabe", "req": ["astrolabe", "compass"], "desc": "A simplified heavy astrolabe used by Portuguese navigators to measure latitude at sea."},
{"id": "backstaff", "name": "Backstaff", "year": 1594, "cat": "instruments", "wiki": "Backstaff", "req": ["cross_staff"], "desc": "John Davis' backstaff measured the sun's altitude by its shadow, sparing the navigator's eyes."},
{"id": "chip_log", "name": "Chip log", "year": 1574, "cat": "instruments", "wiki": "Chip log", "req": ["hourglass", "cordage", "mechanical_clock"], "desc": "A knotted line timed with a sandglass to measure ship speed, the origin of the knot."},
{"id": "dead_reckoning", "name": "Dead reckoning", "year": 1574, "cat": "instruments", "wiki": "Dead reckoning", "req": ["compass", "chip_log"], "desc": "Estimating position from known heading, speed and elapsed time, the basis of pre-modern navigation."},
{"id": "octant", "name": "Octant", "year": 1731, "cat": "instruments", "wiki": "Octant (instrument)", "req": ["backstaff", "reflecting_telescope"], "desc": "John Hadley's double-reflecting octant measured angles accurately from a moving deck."},
{"id": "sextant", "name": "Sextant", "year": 1757, "cat": "instruments", "wiki": "Sextant", "req": ["octant"], "desc": "An extended reflecting instrument that measured lunar distances and altitudes for celestial navigation."},
{"id": "gyroscope", "name": "Gyroscope", "year": 1852, "cat": "instruments", "wiki": "Gyroscope", "req": ["classical_mechanics"], "desc": "Léon Foucault named and used the gyroscope to demonstrate Earth's rotation."},
{"id": "foucault_pendulum", "name": "Foucault pendulum", "year": 1851, "cat": "instruments", "wiki": "Foucault pendulum", "req": ["pendulum"], "desc": "A long free pendulum whose swing plane rotates, the first direct demonstration of Earth's rotation."},
{"id": "gyrocompass", "name": "Gyrocompass", "year": 1906, "cat": "instruments", "wiki": "Gyrocompass", "req": ["gyroscope", "electric_motor"], "desc": "Hermann Anschütz-Kaempfe's motor-driven gyroscope pointed to true north, unaffected by a steel hull's magnetism."},
{"id": "accelerometer", "name": "Accelerometer", "year": 1923, "cat": "instruments", "wiki": "Accelerometer", "req": ["classical_mechanics", "electromagnetism"], "desc": "Instruments measuring proper acceleration, essential to inertial guidance and later in phones."},
{"id": "ring_laser_gyroscope", "name": "Ring laser gyroscope", "year": 1963, "cat": "instruments", "wiki": "Ring laser gyroscope", "req": ["laser", "gyroscope"], "desc": "A gyroscope sensing rotation from the Sagnac effect in a laser loop, with no moving parts."},
{"id": "radio_direction_finder", "name": "Radio direction finder", "year": 1906, "cat": "instruments", "wiki": "Direction finding", "req": ["radio"], "desc": "Antennas finding the bearing of a radio transmitter, used for ship and aircraft navigation."},
{"id": "loran", "name": "LORAN", "year": 1942, "cat": "instruments", "wiki": "LORAN", "req": ["radio_direction_finder", "radar"], "desc": "A hyperbolic radio navigation system timing pulses from shore stations to fix positions at sea."},
{"id": "echo_sounding", "name": "Echo sounding", "year": 1913, "cat": "instruments", "wiki": "Echo sounding", "req": ["telephone"], "desc": "Alexander Behm's method measured water depth by timing sound echoes from the seabed."},
{"id": "sonar", "name": "Sonar", "year": 1918, "cat": "instruments", "wiki": "Sonar", "req": ["echo_sounding", "piezoelectricity", "vacuum_tube"], "desc": "Active underwater sound ranging, developed in the First World War with piezoelectric quartz transducers."},
{"id": "laser_rangefinder", "name": "Laser rangefinder", "year": 1961, "cat": "instruments", "wiki": "Laser rangefinder", "req": ["laser"], "desc": "Timing laser pulses to measure distance, first demonstrated by Hughes Aircraft in 1961."},
{"id": "lidar", "name": "Lidar", "year": 1963, "cat": "instruments", "wiki": "Lidar", "req": ["laser_rangefinder", "radar"], "desc": "Laser-based ranging and mapping, first used for atmospheric and lunar measurements."},
{"id": "total_station", "name": "Total station", "year": 1971, "cat": "instruments", "wiki": "Total station", "req": ["theodolite", "laser_rangefinder", "microprocessor"], "desc": "An electronic theodolite with built-in distance measurement and computation, now standard in surveying."},
{"id": "multimeter", "name": "Multimeter", "year": 1923, "cat": "instruments", "wiki": "Multimeter", "req": ["ammeter"], "desc": "Donald Macadie's AVO meter combined current, voltage and resistance measurement in one instrument."},
{"id": "magnetometer", "name": "Magnetometer", "year": 1832, "cat": "instruments", "wiki": "Magnetometer", "req": ["compass", "electromagnetism"], "desc": "Carl Friedrich Gauss built the first instrument for absolute measurement of magnetic field strength."},
{"id": "ph_meter", "name": "pH meter", "year": 1934, "cat": "instruments", "wiki": "PH meter", "req": ["vacuum_tube", "electrolysis"], "desc": "Arnold Beckman's electronic pH meter measured acidity precisely for chemistry and industry."},
{"id": "dispersive_prism", "name": "Dispersive prism", "year": 1666, "cat": "instruments", "wiki": "Dispersive prism", "req": ["glass", "scientific_method"], "desc": "Isaac Newton used glass prisms to show white light is a mixture of colours."},
{"id": "diffraction_grating", "name": "Diffraction grating", "year": 1821, "cat": "instruments", "wiki": "Diffraction grating", "req": ["glass", "ruler"], "desc": "Joseph von Fraunhofer's ruled wire and glass gratings measured wavelengths of light."},
{"id": "fraunhofer_lines", "name": "Fraunhofer lines", "year": 1814, "cat": "instruments", "wiki": "Fraunhofer lines", "req": ["dispersive_prism", "refracting_telescope"], "desc": "Fraunhofer mapped dark lines in the solar spectrum, later explained as chemical signatures."},
{"id": "spectroscope", "name": "Spectroscope", "year": 1859, "cat": "instruments", "wiki": "Optical spectrometer", "req": ["fraunhofer_lines", "diffraction_grating"], "desc": "Kirchhoff and Bunsen's spectroscope identified elements by their spectral lines, discovering caesium and rubidium."},
{"id": "astronomical_spectroscopy", "name": "Astronomical spectroscopy", "year": 1863, "cat": "instruments", "wiki": "Astronomical spectroscopy", "req": ["spectroscope", "telescope"], "desc": "William Huggins and Angelo Secchi used spectra to determine the composition of stars."},
{"id": "infrared_spectroscopy", "name": "Infrared spectroscopy", "year": 1905, "cat": "instruments", "wiki": "Infrared spectroscopy", "req": ["spectroscope", "bolometer"], "desc": "William Coblentz's infrared spectra of compounds made molecular structure identification possible."},
{"id": "raman_spectroscopy", "name": "Raman spectroscopy", "year": 1928, "cat": "instruments", "wiki": "Raman spectroscopy", "req": ["spectroscope", "quantum_mechanics"], "desc": "C. V. Raman's discovery of inelastic light scattering gave a new probe of molecular vibrations."},
{"id": "spectrophotometer", "name": "Spectrophotometer", "year": 1940, "cat": "instruments", "wiki": "Spectrophotometry", "req": ["spectroscope", "vacuum_tube", "phototube"], "desc": "The Beckman DU made fast quantitative measurement of light absorption routine in laboratories."},
{"id": "ftir", "name": "Fourier-transform infrared spectroscopy", "year": 1969, "cat": "instruments", "wiki": "Fourier-transform infrared spectroscopy", "req": ["infrared_spectroscopy", "michelson_interferometer", "electronic_computer", "fast_fourier_transform"], "desc": "Interferometer-based infrared spectrometers using computed Fourier transforms greatly improved speed and sensitivity."},
{"id": "mass_spectrometry", "name": "Mass spectrometry", "year": 1912, "cat": "instruments", "wiki": "Mass spectrometry", "req": ["cathode_ray_tube", "electromagnet", "vacuum_pump", "electron"], "desc": "J. J. Thomson's parabola apparatus separated ions by mass, revealing isotopes of neon."},
{"id": "gas_chromatography", "name": "Gas chromatography", "year": 1952, "cat": "instruments", "wiki": "Gas chromatography", "req": ["chromatography"], "desc": "James and Martin's gas-liquid chromatography separated volatile compounds quickly and precisely."},
{"id": "gc_ms", "name": "Gas chromatography–mass spectrometry", "year": 1956, "cat": "instruments", "wiki": "Gas chromatography–mass spectrometry", "req": ["gas_chromatography", "mass_spectrometry"], "desc": "Coupling a gas chromatograph to a mass spectrometer allowed identification of substances in complex mixtures."},
{"id": "nmr_spectroscopy", "name": "NMR spectroscopy", "year": 1946, "cat": "instruments", "wiki": "Nuclear magnetic resonance spectroscopy", "req": ["quantum_mechanics", "electromagnet", "radio"], "desc": "Bloch and Purcell detected nuclear magnetic resonance in bulk matter, later the chemist's main structural tool."},
{"id": "neutron_diffraction", "name": "Neutron diffraction", "year": 1946, "cat": "instruments", "wiki": "Neutron diffraction", "req": ["nuclear_reactor", "x_ray_crystallography", "neutron"], "desc": "Clifford Shull and Ernest Wollan used reactor neutrons to determine atomic and magnetic structures."},
{"id": "michelson_interferometer", "name": "Michelson interferometer", "year": 1881, "cat": "instruments", "wiki": "Michelson interferometer", "req": ["dispersive_prism", "refracting_telescope"], "desc": "Albert Michelson's interferometer measured lengths to fractions of a wavelength and tested the ether hypothesis."},
{"id": "fabry_perot", "name": "Fabry–Pérot interferometer", "year": 1899, "cat": "instruments", "wiki": "Fabry–Pérot interferometer", "req": ["michelson_interferometer"], "desc": "A pair of parallel mirrors producing sharp interference fringes, later the resonator of lasers."},
{"id": "holography", "name": "Holography", "year": 1947, "cat": "instruments", "wiki": "Holography", "req": ["electron_microscope", "michelson_interferometer"], "desc": "Dennis Gabor invented holography to improve electron microscopy; lasers made it practical in 1962."},
{"id": "optical_tweezers", "name": "Optical tweezers", "year": 1986, "cat": "instruments", "wiki": "Optical tweezers", "req": ["laser", "microscope"], "desc": "Arthur Ashkin's focused laser beam trapped and moved particles and living cells."},
{"id": "radio_telescope", "name": "Radio telescope", "year": 1937, "cat": "instruments", "wiki": "Radio telescope", "req": ["radio"], "desc": "Grote Reber's dish followed Karl Jansky's 1932 detection of cosmic radio waves and founded radio astronomy."},
{"id": "aperture_synthesis", "name": "Aperture synthesis", "year": 1946, "cat": "instruments", "wiki": "Aperture synthesis", "req": ["radio_telescope", "electronic_computer"], "desc": "Martin Ryle combined signals from separated antennas to synthesize the resolution of a much larger telescope."},
{"id": "vlbi", "name": "Very-long-baseline interferometry", "year": 1967, "cat": "instruments", "wiki": "Very-long-baseline interferometry", "req": ["aperture_synthesis", "atomic_clock"], "desc": "Telescopes thousands of kilometres apart recorded signals with atomic clocks and combined them later."},
{"id": "event_horizon_telescope", "name": "Event Horizon Telescope", "year": 2019, "cat": "instruments", "wiki": "Event Horizon Telescope", "req": ["vlbi", "hydrogen_maser"], "desc": "A planet-wide VLBI array that produced the first image of a black hole's shadow, in galaxy M87."},
{"id": "ligo", "name": "LIGO", "year": 2015, "cat": "instruments", "wiki": "LIGO", "req": ["michelson_interferometer", "laser", "fabry_perot"], "desc": "Kilometre-scale laser interferometers that made the first direct detection of gravitational waves in 2015."},
{"id": "liquefaction_of_gases", "name": "Liquefaction of gases", "year": 1877, "cat": "instruments", "wiki": "Liquefaction of gases", "req": ["thermodynamics", "vacuum_pump", "refrigeration"], "desc": "Cailletet and Pictet first liquefied oxygen, opening the field of cryogenics."},
{"id": "hampson_linde_cycle", "name": "Hampson–Linde cycle", "year": 1895, "cat": "instruments", "wiki": "Hampson–Linde cycle", "req": ["liquefaction_of_gases"], "desc": "A regenerative throttling process that made liquid air production practical and industrial."},
{"id": "liquid_helium", "name": "Liquefaction of helium", "year": 1908, "cat": "instruments", "wiki": "Liquid helium", "req": ["hampson_linde_cycle", "vacuum_flask", "air_separation"], "desc": "Heike Kamerlingh Onnes liquefied helium at 4 K, enabling low-temperature physics."},
{"id": "dilution_refrigerator", "name": "Dilution refrigerator", "year": 1965, "cat": "instruments", "wiki": "Dilution refrigerator", "req": ["liquid_helium"], "desc": "A helium-3/helium-4 refrigerator reaching millikelvin temperatures continuously."},
{"id": "squid", "name": "SQUID", "year": 1964, "cat": "instruments", "wiki": "SQUID", "req": ["superconductivity", "quantum_mechanics"], "desc": "A superconducting loop with Josephson junctions, the most sensitive magnetometer known."},
{"id": "superconducting_magnet", "name": "Superconducting magnet", "year": 1961, "cat": "instruments", "wiki": "Superconducting magnet", "req": ["superconductivity", "electromagnet", "niobium_tin"], "desc": "Niobium alloy wire carrying lossless current produced strong steady fields for accelerators and MRI."},
{"id": "cloud_chamber", "name": "Cloud chamber", "year": 1911, "cat": "instruments", "wiki": "Cloud chamber", "req": ["x_ray", "thermodynamics"], "desc": "C. T. R. Wilson's chamber made tracks of charged particles visible as condensation trails."},
{"id": "geiger_counter", "name": "Geiger counter", "year": 1928, "cat": "instruments", "wiki": "Geiger counter", "req": ["vacuum_tube", "x_ray", "radioactivity"], "desc": "The Geiger–Müller tube gave a simple, portable detector of ionizing radiation."},
{"id": "scintillation_counter", "name": "Scintillation counter", "year": 1944, "cat": "instruments", "wiki": "Scintillation counter", "req": ["photomultiplier"], "desc": "Samuel Curran coupled a scintillating crystal to a photomultiplier to count radiation precisely."},
{"id": "bubble_chamber", "name": "Bubble chamber", "year": 1952, "cat": "instruments", "wiki": "Bubble chamber", "req": ["cloud_chamber", "liquefaction_of_gases"], "desc": "Donald Glaser's superheated-liquid detector recorded high-energy particle tracks in fine detail."},
{"id": "wire_chamber", "name": "Wire chamber", "year": 1968, "cat": "instruments", "wiki": "Wire chamber", "req": ["geiger_counter", "electronic_computer"], "desc": "Georges Charpak's multiwire proportional chamber read particle tracks electronically at high rates."},
{"id": "neutrino_detector", "name": "Neutrino detector", "year": 1956, "cat": "instruments", "wiki": "Neutrino detector", "req": ["scintillation_counter", "nuclear_reactor"], "desc": "Cowan and Reines first detected neutrinos from a reactor using large liquid scintillator tanks."},
{"id": "super_kamiokande", "name": "Super-Kamiokande", "year": 1996, "cat": "instruments", "wiki": "Super-Kamiokande", "req": ["neutrino_detector", "photomultiplier"], "desc": "A giant water Cherenkov detector in Japan that discovered neutrino oscillations in 1998."},
{"id": "cockcroft_walton", "name": "Cockcroft–Walton generator", "year": 1932, "cat": "instruments", "wiki": "Cockcroft–Walton generator", "req": ["transformer", "vacuum_tube"], "desc": "A voltage multiplier that accelerated protons to split lithium nuclei, the first artificial nuclear disintegration."},
{"id": "linear_accelerator", "name": "Linear particle accelerator", "year": 1928, "cat": "instruments", "wiki": "Linear particle accelerator", "req": ["vacuum_tube", "radio", "radiation_therapy"], "desc": "Rolf Widerøe's linac accelerated ions with alternating fields along a straight line of drift tubes."},
{"id": "cyclotron", "name": "Cyclotron", "year": 1931, "cat": "instruments", "wiki": "Cyclotron", "req": ["electromagnet", "vacuum_pump", "radio"], "desc": "Ernest Lawrence's cyclotron accelerated particles in a spiral within a magnetic field."},
{"id": "synchrotron", "name": "Synchrotron", "year": 1945, "cat": "instruments", "wiki": "Synchrotron", "req": ["cyclotron"], "desc": "An accelerator synchronizing its magnetic field with particle energy, allowing far higher energies."},
{"id": "synchrotron_light_source", "name": "Synchrotron light source", "year": 1970, "cat": "instruments", "wiki": "Synchrotron light source", "req": ["synchrotron", "x_ray_crystallography"], "desc": "Storage rings dedicated to producing intense X-rays for structural biology and materials science."},
{"id": "collider", "name": "Particle collider", "year": 1961, "cat": "instruments", "wiki": "Collider", "req": ["synchrotron"], "desc": "Storage rings colliding opposing beams, beginning with AdA in Frascati, raised available collision energy."},
{"id": "tevatron", "name": "Tevatron", "year": 1983, "cat": "instruments", "wiki": "Tevatron", "req": ["collider", "superconducting_magnet"], "desc": "Fermilab's superconducting proton-antiproton collider discovered the top quark in 1995."},
{"id": "lhc", "name": "Large Hadron Collider", "year": 2008, "cat": "instruments", "wiki": "Large Hadron Collider", "req": ["tevatron", "superconducting_magnet", "wire_chamber"], "desc": "CERN's 27-kilometre collider, the most powerful accelerator built, discovered the Higgs boson in 2012."},
{"id": "steelyard_balance", "name": "Steelyard balance", "year": -400, "cat": "instruments", "wiki": "Steelyard balance", "req": ["balance_scale", "lever"], "desc": "An unequal-arm balance with a sliding counterweight that weighed heavy loads with a single small mass."},
{"id": "spring_scale", "name": "Spring scale", "year": 1770, "cat": "instruments", "wiki": "Spring scale", "req": ["steel", "hookes_law"], "desc": "A scale that measures weight by the extension of a steel spring, first made in Britain around 1770."},
{"id": "gauge_block", "name": "Gauge block", "year": 1896, "cat": "instruments", "wiki": "Gauge block", "req": ["machine_tools", "units_of_measurement", "micrometer_gauge", "steel", "surface_plate"], "desc": "Carl Edvard Johansson's precision steel blocks became the reference standard for workshop length measurement."},
{"id": "kibble_balance", "name": "Kibble balance", "year": 1975, "cat": "instruments", "wiki": "Kibble balance", "req": ["analytical_balance", "electromagnet", "michelson_interferometer"], "desc": "Bryan Kibble's watt balance related mass to electrical quantities and Planck's constant, enabling a new kilogram definition."},
{"id": "si_2019", "name": "2019 SI redefinition", "year": 2019, "cat": "instruments", "wiki": "2019 revision of the SI", "req": ["si_units", "kibble_balance", "caesium_standard"], "desc": "All SI base units were redefined by fixed values of physical constants, retiring the physical kilogram artefact."},
{"id": "fusee", "name": "Fusee", "year": 1490, "cat": "instruments", "wiki": "Fusee (horology)", "req": ["mainspring"], "desc": "A cone-shaped pulley that evened out a mainspring's declining force to keep spring clocks accurate."},
{"id": "chronograph", "name": "Chronograph", "year": 1816, "cat": "instruments", "wiki": "Chronograph", "req": ["pocket_watch"], "desc": "A watch with an independent stopwatch function, first built by Louis Moinet for astronomical timing."},
{"id": "gridiron_pendulum", "name": "Gridiron pendulum", "year": 1726, "cat": "instruments", "wiki": "Gridiron pendulum", "req": ["pendulum_clock"], "desc": "John Harrison's pendulum of alternating brass and steel rods compensated for thermal expansion."},
{"id": "shortt_clock", "name": "Shortt–Synchronome clock", "year": 1921, "cat": "instruments", "wiki": "Shortt–Synchronome clock", "req": ["electric_clock", "pendulum_clock"], "desc": "A free-pendulum electromechanical clock that was the most accurate timekeeper until quartz clocks."},
{"id": "chip_scale_atomic_clock", "name": "Chip-scale atomic clock", "year": 2004, "cat": "instruments", "wiki": "Chip-scale atomic clock", "req": ["caesium_standard", "integrated_circuit", "laser"], "desc": "NIST shrank an atomic frequency reference to a few cubic millimetres, enabling portable atomic timing."},
{"id": "magneto_optical_trap", "name": "Magneto-optical trap", "year": 1987, "cat": "instruments", "wiki": "Magneto-optical trap", "req": ["laser_cooling"], "desc": "A device combining lasers and a magnetic field gradient to capture and cool clouds of neutral atoms."},
{"id": "bose_einstein_condensate", "name": "Bose–Einstein condensate", "year": 1995, "cat": "instruments", "wiki": "Bose–Einstein condensate", "req": ["magneto_optical_trap"], "desc": "Cornell and Wieman first produced this ultracold state of matter in rubidium atoms in 1995."},
{"id": "binoculars", "name": "Binoculars", "year": 1854, "cat": "instruments", "wiki": "Binoculars", "req": ["achromatic_lens"], "desc": "Ignazio Porro's prism erecting system made compact high-power binoculars possible."},
{"id": "schmidt_camera", "name": "Schmidt camera", "year": 1930, "cat": "instruments", "wiki": "Schmidt camera", "req": ["reflecting_telescope"], "desc": "Bernhard Schmidt's wide-field telescope used a corrector plate to photograph large areas of sky sharply."},
{"id": "coronagraph", "name": "Coronagraph", "year": 1931, "cat": "instruments", "wiki": "Coronagraph", "req": ["refracting_telescope"], "desc": "Bernard Lyot's instrument blocked the solar disc to observe the corona without an eclipse."},
{"id": "transit_instrument", "name": "Transit instrument", "year": 1690, "cat": "instruments", "wiki": "Transit instrument", "req": ["telescope", "pendulum_clock"], "desc": "Ole Rømer's meridian telescope timed star crossings to fix celestial positions and correct clocks."},
{"id": "spectroheliograph", "name": "Spectroheliograph", "year": 1890, "cat": "instruments", "wiki": "Spectroheliograph", "req": ["spectroscope", "astrophotography"], "desc": "George Ellery Hale's instrument photographed the Sun in a single wavelength of light."},
{"id": "orrery", "name": "Orrery", "year": 1713, "cat": "instruments", "wiki": "Orrery", "req": ["gear", "classical_mechanics"], "desc": "Geared models of the solar system demonstrated planetary motions for teaching."},
{"id": "planimeter", "name": "Planimeter", "year": 1814, "cat": "instruments", "wiki": "Planimeter", "req": ["calculus"], "desc": "A mechanical integrator that measures the area of a plane figure by tracing its boundary."},
{"id": "oil_immersion", "name": "Oil immersion objective", "year": 1840, "cat": "instruments", "wiki": "Oil immersion", "req": ["microscope", "achromatic_lens"], "desc": "Immersing the objective in oil raised a microscope's numerical aperture and resolution."},
{"id": "ultramicroscope", "name": "Ultramicroscope", "year": 1902, "cat": "instruments", "wiki": "Ultramicroscope", "req": ["microscope"], "desc": "Siedentopf and Zsigmondy's dark-field instrument revealed colloidal particles below the optical resolution limit."},
{"id": "merkhet", "name": "Merkhet", "year": -600, "cat": "instruments", "wiki": "Merkhet", "req": ["cordage", "calendar"], "desc": "An Egyptian plumb-line sighting tool used to align buildings and time the night by star transits."},
{"id": "torquetum", "name": "Torquetum", "year": 1284, "cat": "instruments", "wiki": "Torquetum", "req": ["astrolabe"], "desc": "A medieval astronomical instrument converting between celestial coordinate systems."},
{"id": "weather_vane", "name": "Weather vane", "year": -50, "cat": "instruments", "wiki": "Weather vane", "req": ["bronze"], "desc": "Indicators of wind direction, notably the Triton on Athens' Tower of the Winds."},
{"id": "hydrometer", "name": "Hydrometer", "year": 400, "cat": "instruments", "wiki": "Hydrometer", "req": ["glass", "balance_scale"], "desc": "A floating instrument measuring liquid density, described in letters to Hypatia of Alexandria."},
{"id": "thermographic_camera", "name": "Thermographic camera", "year": 1929, "cat": "instruments", "wiki": "Thermography", "req": ["bolometer", "vacuum_tube"], "desc": "Cameras imaging infrared radiation, first built by Kálmán Tihanyi and developed for military night use."},
{"id": "decca_navigator", "name": "Decca Navigator System", "year": 1944, "cat": "instruments", "wiki": "Decca Navigator System", "req": ["radio_direction_finder"], "desc": "A British hyperbolic system using phase comparison of continuous radio signals, first used on D-Day."},
{"id": "plane_table", "name": "Plane table", "year": 1551, "cat": "instruments", "wiki": "Plane table", "req": ["surveying"], "desc": "A drawing board on a tripod used to plot survey maps directly in the field."},
{"id": "gunters_chain", "name": "Gunter's chain", "year": 1620, "cat": "instruments", "wiki": "Gunter's chain", "req": ["surveying", "units_of_measurement"], "desc": "Edmund Gunter's 66-foot measuring chain standardized land surveying in Britain and its colonies."},
{"id": "tellurometer", "name": "Tellurometer", "year": 1954, "cat": "instruments", "wiki": "Tellurometer", "req": ["radar", "surveying"], "desc": "Trevor Wadley's microwave distance meter measured survey lines of tens of kilometres electronically."},
{"id": "fiber_optic_gyroscope", "name": "Fibre-optic gyroscope", "year": 1976, "cat": "instruments", "wiki": "Fibre-optic gyroscope", "req": ["ring_laser_gyroscope", "optical_fiber"], "desc": "A rotation sensor using light in a coil of optical fibre, compact and robust for navigation."},
{"id": "epr_spectroscopy", "name": "Electron paramagnetic resonance", "year": 1944, "cat": "instruments", "wiki": "Electron paramagnetic resonance", "req": ["quantum_mechanics", "radar"], "desc": "Yevgeny Zavoisky detected resonant absorption by unpaired electrons in a magnetic field."},
{"id": "spark_chamber", "name": "Spark chamber", "year": 1959, "cat": "instruments", "wiki": "Spark chamber", "req": ["geiger_counter"], "desc": "A gas detector where sparks along particle paths recorded tracks, used to discover the muon neutrino."},
{"id": "betatron", "name": "Betatron", "year": 1940, "cat": "instruments", "wiki": "Betatron", "req": ["transformer", "cyclotron"], "desc": "Donald Kerst's betatron accelerated electrons with a changing magnetic field."},
{"id": "free_electron_laser", "name": "Free-electron laser", "year": 1976, "cat": "instruments", "wiki": "Free-electron laser", "req": ["linear_accelerator", "laser"], "desc": "John Madey's laser generated tunable coherent light from relativistic electrons in an undulator."},
{"id": "wedge", "name": "Wedge", "year": -1760000, "cat": "manufacturing", "wiki": "Wedge", "req": ["hand_axe"], "desc": "A tapered tool that converts a driving force into splitting force; the working principle behind blades, axes and chisels."},
{"id": "axe", "name": "Axe", "year": -44000, "cat": "manufacturing", "wiki": "Axe", "req": ["hafting", "hand_axe"], "desc": "A hafted blade swung to fell trees and split wood; enabled forest clearance and timber building."},
{"id": "hammer", "name": "Hammer", "year": -30000, "cat": "manufacturing", "wiki": "Hammer", "req": ["hafting"], "desc": "A hafted striking tool that delivers concentrated impact for shaping, driving and forging."},
{"id": "spindle", "name": "Spindle", "year": -10000, "cat": "manufacturing", "wiki": "Spindle (textiles)", "req": ["cordage"], "desc": "A weighted rod spun by hand to twist fibers into yarn, the basis of all spinning for millennia."},
{"id": "chisel", "name": "Chisel", "year": -8000, "cat": "manufacturing", "wiki": "Chisel", "req": ["hammer", "ground_stone"], "desc": "A wedge-edged blade driven by a mallet to cut and shape wood, stone and later metal."},
{"id": "forging", "name": "Forging", "year": -4000, "cat": "manufacturing", "wiki": "Forging", "req": ["smelting", "hammer"], "desc": "Shaping heated metal by hammering, the basic method of making tools and weapons for millennia."},
{"id": "lost_wax_casting", "name": "Lost-wax casting", "year": -3700, "cat": "manufacturing", "wiki": "Lost-wax casting", "req": ["smelting", "pottery"], "desc": "Casting metal in a mould formed around a wax model that is melted out, allowing intricate detail."},
{"id": "wheel_and_axle", "name": "Wheel and axle", "year": -3500, "cat": "manufacturing", "wiki": "Wheel and axle", "req": ["wheel"], "desc": "A simple machine in which a wheel fixed to a shaft multiplies torque, the basis of winches and cranks."},
{"id": "metal_casting", "name": "Metal casting", "year": -3200, "cat": "manufacturing", "wiki": "Metal casting", "req": ["smelting", "pottery", "crucible"], "desc": "Pouring molten metal into a mould to make complex shapes in one step."},
{"id": "saw", "name": "Saw", "year": -3100, "cat": "manufacturing", "wiki": "Saw", "req": ["smelting", "stone_tools"], "desc": "A toothed blade for cutting wood and stone; copper saws appear in early Egyptian woodworking."},
{"id": "anvil", "name": "Anvil", "year": -3000, "cat": "manufacturing", "wiki": "Anvil", "req": ["forging", "bronze"], "desc": "A heavy metal block on which hot metal is hammered into shape."},
{"id": "rivet", "name": "Rivet", "year": -3000, "cat": "manufacturing", "wiki": "Rivet", "req": ["bronze", "hammer"], "desc": "A metal pin hammered over at both ends to join plates; later key to boilers, ships, bridges and aircraft."},
{"id": "inclined_plane", "name": "Inclined plane", "year": -2600, "cat": "manufacturing", "wiki": "Inclined plane", "req": ["mudbrick", "cordage"], "desc": "A ramp that trades distance for force, used to raise heavy stones for Egyptian and Mesopotamian monuments."},
{"id": "file_tool", "name": "File", "year": -1200, "cat": "manufacturing", "wiki": "File (tool)", "req": ["iron_working"], "desc": "A hardened bar with cut teeth for removing metal, essential for fitting parts before machine tools."},
{"id": "forge_welding", "name": "Forge welding", "year": -1200, "cat": "manufacturing", "wiki": "Forge welding", "req": ["forging", "iron_working", "wrought_iron"], "desc": "Joining iron pieces by heating them to near melting and hammering them together; the oldest welding method."},
{"id": "winch", "name": "Winch", "year": -400, "cat": "manufacturing", "wiki": "Winch", "req": ["wheel_and_axle", "cordage"], "desc": "A drum turned by a crank to wind a rope, giving mechanical advantage for hauling and lifting."},
{"id": "block_and_tackle", "name": "Block and tackle", "year": -250, "cat": "manufacturing", "wiki": "Block and tackle", "req": ["pulley", "cordage"], "desc": "A system of multiple pulleys that multiplies lifting force; attributed to Archimedes."},
{"id": "archimedes_screw", "name": "Archimedes' screw", "year": -250, "cat": "manufacturing", "wiki": "Archimedes' screw", "req": ["screw"], "desc": "A helical surface inside a tube that lifts water when turned, used for irrigation and draining mines."},
{"id": "treadwheel_crane", "name": "Treadwheel crane", "year": -230, "cat": "manufacturing", "wiki": "Treadwheel crane", "req": ["crane_machine", "wheel_and_axle"], "desc": "A crane powered by people walking inside a large wheel, used from Roman times through medieval cathedral building."},
{"id": "worm_drive", "name": "Worm drive", "year": -200, "cat": "manufacturing", "wiki": "Worm drive", "req": ["gear", "screw"], "desc": "A screw meshing with a gear to give a large speed reduction and self-locking action."},
{"id": "cam", "name": "Cam", "year": -200, "cat": "manufacturing", "wiki": "Cam (mechanism)", "req": ["wheel_and_axle"], "desc": "A rotating profile that converts rotary motion into reciprocating or timed motion."},
{"id": "trip_hammer", "name": "Trip hammer", "year": -100, "cat": "manufacturing", "wiki": "Trip hammer", "req": ["cam", "hammer", "water_wheel"], "desc": "A heavy hammer raised by cams on a water-driven shaft, used in China and Europe for forging, hulling and fulling."},
{"id": "belt_drive", "name": "Belt drive", "year": -100, "cat": "manufacturing", "wiki": "Belt (mechanical)", "req": ["wheel_and_axle", "cordage"], "desc": "A loop of flexible material transmitting rotation between pulleys; used on early Chinese quilling and spinning wheels."},
{"id": "crank", "name": "Crank", "year": -100, "cat": "manufacturing", "wiki": "Crank (mechanism)", "req": ["wheel_and_axle"], "desc": "An arm at right angles to a shaft that converts between rotary and reciprocating motion."},
{"id": "plane_tool", "name": "Hand plane", "year": 1, "cat": "manufacturing", "wiki": "Plane (tool)", "req": ["chisel", "iron_working"], "desc": "A blade held in a body at a fixed depth for flattening and smoothing wood; known from Roman sites."},
{"id": "bearing", "name": "Bearing", "year": 40, "cat": "manufacturing", "wiki": "Bearing (mechanical)", "req": ["wheel_and_axle"], "desc": "A machine element that supports a rotating shaft and reduces friction; rolling bearings are known from Roman ships at Nemi."},
{"id": "screw_press", "name": "Screw press", "year": 50, "cat": "manufacturing", "wiki": "Screw press", "req": ["screw"], "desc": "A press driven by a large screw, used by Romans for olives and grapes and later for printing and coining."},
{"id": "connecting_rod", "name": "Connecting rod", "year": 250, "cat": "manufacturing", "wiki": "Connecting rod", "req": ["crank"], "desc": "A rod linking a crank to a reciprocating part such as a saw frame or piston."},
{"id": "hierapolis_sawmill", "name": "Hierapolis sawmill", "year": 250, "cat": "manufacturing", "wiki": "Hierapolis sawmill", "req": ["water_wheel", "crank", "connecting_rod", "saw"], "desc": "A Roman water-powered stone sawmill, the earliest known machine combining a crank and connecting rod."},
{"id": "spinning_wheel", "name": "Spinning wheel", "year": 1000, "cat": "manufacturing", "wiki": "Spinning wheel", "req": ["spindle", "belt_drive"], "desc": "A hand- or foot-driven wheel that turns a spindle by a belt, greatly speeding up yarn production."},
{"id": "knitting", "name": "Knitting", "year": 1000, "cat": "manufacturing", "wiki": "Knitting", "req": ["sewing_needle", "cordage"], "desc": "Forming fabric from interlocking loops of yarn using needles; known from Egyptian socks around 1000 CE."},
{"id": "chain_drive", "name": "Chain drive", "year": 1090, "cat": "manufacturing", "wiki": "Chain drive", "req": ["gear"], "desc": "Transmitting power through an endless chain over sprockets; used in Su Song's astronomical clock tower."},
{"id": "flywheel", "name": "Flywheel", "year": 1100, "cat": "manufacturing", "wiki": "Flywheel", "req": ["wheel_and_axle", "potters_wheel"], "desc": "A heavy wheel that stores rotational energy to smooth out uneven power input."},
{"id": "pole_lathe", "name": "Pole lathe", "year": 1200, "cat": "manufacturing", "wiki": "Pole lathe", "req": ["lathe"], "desc": "A lathe driven by a cord wound around the work and tensioned by a springy pole and treadle."},
{"id": "crankshaft", "name": "Crankshaft", "year": 1206, "cat": "manufacturing", "wiki": "Crankshaft", "req": ["crank", "connecting_rod"], "desc": "A shaft with offset crank throws driving or driven by several connecting rods; described by al-Jazari."},
{"id": "camshaft", "name": "Camshaft", "year": 1206, "cat": "manufacturing", "wiki": "Camshaft", "req": ["cam"], "desc": "A shaft carrying several cams that operate valves or hammers in sequence; described by al-Jazari."},
{"id": "sawmill", "name": "Sawmill", "year": 1225, "cat": "manufacturing", "wiki": "Sawmill", "req": ["saw", "water_wheel", "crank"], "desc": "A mill using water or later steam power to saw logs into timber."},
{"id": "spring", "name": "Spring", "year": 1400, "cat": "manufacturing", "wiki": "Spring (device)", "req": ["steel"], "desc": "An elastic metal device that stores mechanical energy, used in locks, clocks and later every kind of machine."},
{"id": "brace_tool", "name": "Brace", "year": 1420, "cat": "manufacturing", "wiki": "Brace (tool)", "req": ["crank", "bow_drill"], "desc": "A hand drill turned by a cranked handle, giving continuous rotation for boring holes."},
{"id": "nut_and_bolt", "name": "Nut and bolt", "year": 1450, "cat": "manufacturing", "wiki": "Nut (hardware)", "req": ["screw", "lathe"], "desc": "A threaded fastener pair that clamps parts and can be undone, the standard way of assembling machines."},
{"id": "stocking_frame", "name": "Stocking frame", "year": 1589, "cat": "manufacturing", "wiki": "Stocking frame", "req": ["knitting", "spring"], "desc": "William Lee's mechanical knitting machine, one of the first major textile machines."},
{"id": "rolling_mill", "name": "Rolling mill", "year": 1590, "cat": "manufacturing", "wiki": "Rolling (metalworking)", "req": ["water_wheel", "cast_iron", "gear", "wrought_iron"], "desc": "Passing metal between rollers to reduce thickness and make uniform sheet and bar."},
{"id": "flying_shuttle", "name": "Flying shuttle", "year": 1733, "cat": "manufacturing", "wiki": "Flying shuttle", "req": ["weaving"], "desc": "John Kay's shuttle propelled across the loom by a picker, doubling weaving speed."},
{"id": "carding_machine", "name": "Carding machine", "year": 1748, "cat": "manufacturing", "wiki": "Carding", "req": ["spinning_wheel", "gear"], "desc": "Machines with wire-toothed cylinders that disentangle and align fibers before spinning."},
{"id": "spinning_jenny", "name": "Spinning jenny", "year": 1764, "cat": "manufacturing", "wiki": "Spinning jenny", "req": ["spinning_wheel"], "desc": "Hargreaves's multi-spindle spinning frame that let one worker spin many threads at once."},
{"id": "water_frame", "name": "Water frame", "year": 1769, "cat": "manufacturing", "wiki": "Water frame", "req": ["spinning_wheel", "water_wheel", "gear"], "desc": "Arkwright's water-powered roller spinning machine, which led to the first cotton mills."},
{"id": "circular_saw", "name": "Circular saw", "year": 1777, "cat": "manufacturing", "wiki": "Circular saw", "req": ["saw", "water_wheel"], "desc": "A toothed disc rotating continuously, much faster than a reciprocating saw."},
{"id": "spinning_mule", "name": "Spinning mule", "year": 1779, "cat": "manufacturing", "wiki": "Spinning mule", "req": ["spinning_jenny", "water_frame"], "desc": "Crompton's combination of jenny and water frame that spun fine, strong yarn."},
{"id": "power_loom", "name": "Power loom", "year": 1785, "cat": "manufacturing", "wiki": "Power loom", "req": ["flying_shuttle", "steam_engine"], "desc": "Cartwright's mechanized loom, which brought weaving into factories."},
{"id": "ball_bearing", "name": "Ball bearing", "year": 1794, "cat": "manufacturing", "wiki": "Ball bearing", "req": ["bearing", "steel"], "desc": "A rolling bearing using hardened balls between races, patented by Philip Vaughan in 1794."},
{"id": "hydraulic_press", "name": "Hydraulic press", "year": 1795, "cat": "manufacturing", "wiki": "Hydraulic press", "req": ["classical_mechanics", "cast_iron", "pascals_law"], "desc": "Bramah's press using Pascal's principle to multiply force, used for forming, baling and extrusion."},
{"id": "extrusion", "name": "Extrusion", "year": 1797, "cat": "manufacturing", "wiki": "Extrusion", "req": ["hydraulic_press"], "desc": "Forcing material through a shaped die to make long profiles; first used by Bramah for lead pipe."},
{"id": "screw_cutting_lathe", "name": "Screw-cutting lathe", "year": 1800, "cat": "manufacturing", "wiki": "Screw-cutting lathe", "req": ["lathe", "screw", "machine_tools"], "desc": "A lathe with a lead screw and change gears that cuts accurate threads; Maudslay's made standard screws possible."},
{"id": "portsmouth_block_mills", "name": "Portsmouth Block Mills", "year": 1803, "cat": "manufacturing", "wiki": "Portsmouth Block Mills", "req": ["machine_tools", "watt_steam_engine"], "desc": "Brunel and Maudslay's steam-powered machines that mass-produced pulley blocks for the Royal Navy."},
{"id": "mass_production", "name": "Mass production", "year": 1803, "cat": "manufacturing", "wiki": "Mass production", "req": ["portsmouth_block_mills", "interchangeable_parts"], "desc": "Making large quantities of standardized products with specialized machines and divided labor."},
{"id": "jacquard_loom", "name": "Jacquard loom", "year": 1804, "cat": "manufacturing", "wiki": "Jacquard machine", "req": ["power_loom"], "desc": "A loom attachment controlled by punched cards, allowing complex patterns and inspiring computing."},
{"id": "band_saw", "name": "Band saw", "year": 1809, "cat": "manufacturing", "wiki": "Bandsaw", "req": ["saw", "steel"], "desc": "A continuous toothed steel band running over wheels, used for curved and resawing cuts."},
{"id": "planer", "name": "Planer", "year": 1817, "cat": "manufacturing", "wiki": "Planer (metalworking)", "req": ["machine_tools"], "desc": "A machine tool that moves the workpiece under a fixed cutter to produce large flat surfaces."},
{"id": "milling_machine", "name": "Milling machine", "year": 1818, "cat": "manufacturing", "wiki": "Milling (machining)", "req": ["machine_tools", "interchangeable_parts", "gear"], "desc": "A machine using rotary multi-tooth cutters to shape metal; key to making interchangeable firearm parts."},
{"id": "ring_spinning", "name": "Ring spinning", "year": 1828, "cat": "manufacturing", "wiki": "Ring spinning", "req": ["water_frame"], "desc": "Continuous spinning using a traveller on a ring, the dominant yarn method of the 20th century."},
{"id": "american_system", "name": "American system of manufacturing", "year": 1830, "cat": "manufacturing", "wiki": "American system of manufacturing", "req": ["interchangeable_parts", "milling_machine"], "desc": "Production with specialized machines, jigs and gauges to make interchangeable parts, pioneered at US armories."},
{"id": "roberts_loom", "name": "Roberts loom", "year": 1830, "cat": "manufacturing", "wiki": "Roberts loom", "req": ["power_loom", "machine_tools"], "desc": "Richard Roberts's cast-iron power loom, the first widely successful one."},
{"id": "sewing_machine", "name": "Sewing machine", "year": 1830, "cat": "manufacturing", "wiki": "Sewing machine", "req": ["sewing_needle", "machine_tools", "crank"], "desc": "A machine that stitches cloth mechanically; Thimonnier's and later Howe's and Singer's designs mechanized garment making."},
{"id": "shaper", "name": "Shaper", "year": 1836, "cat": "manufacturing", "wiki": "Shaper", "req": ["machine_tools", "planer"], "desc": "A machine tool with a reciprocating single-point cutter for flat surfaces and slots."},
{"id": "die_casting", "name": "Die casting", "year": 1838, "cat": "manufacturing", "wiki": "Die casting", "req": ["metal_casting", "movable_type"], "desc": "Forcing molten metal into reusable steel dies under pressure; first used to cast printing type."},
{"id": "steam_hammer", "name": "Steam hammer", "year": 1839, "cat": "manufacturing", "wiki": "Steam hammer", "req": ["watt_steam_engine", "forging"], "desc": "Nasmyth's steam-driven hammer that could forge very large pieces such as ship shafts."},
{"id": "surface_plate", "name": "Surface plate", "year": 1840, "cat": "manufacturing", "wiki": "Surface plate", "req": ["machine_tools"], "desc": "A flat reference plate made by Whitworth's three-plate scraping method, the basis of precision measurement."},
{"id": "whitworth_thread", "name": "Whitworth thread", "year": 1841, "cat": "manufacturing", "wiki": "British Standard Whitworth", "req": ["screw_cutting_lathe"], "desc": "The first national screw thread standard, proposed by Joseph Whitworth."},
{"id": "turret_lathe", "name": "Turret lathe", "year": 1845, "cat": "manufacturing", "wiki": "Turret lathe", "req": ["lathe", "interchangeable_parts"], "desc": "A lathe with an indexing tool turret for repeated operations without resetting tools."},
{"id": "hydraulic_crane", "name": "Hydraulic crane", "year": 1846, "cat": "manufacturing", "wiki": "Hydraulic jigger", "req": ["crane_machine", "hydraulic_press"], "desc": "William Armstrong's crane driven by water pressure, widely used on docks."},
{"id": "go_no_go_gauge", "name": "Go/no-go gauge", "year": 1850, "cat": "manufacturing", "wiki": "Go/no-go gauge", "req": ["interchangeable_parts"], "desc": "A fixed gauge that checks a part is within tolerance, making interchangeable manufacture practical."},
{"id": "hobbing", "name": "Gear hobbing", "year": 1856, "cat": "manufacturing", "wiki": "Hobbing", "req": ["milling_machine", "worm_drive"], "desc": "Generating gear teeth with a rotating helical cutter, the main method of mass-producing gears."},
{"id": "drill_bit", "name": "Twist drill bit", "year": 1861, "cat": "manufacturing", "wiki": "Drill bit", "req": ["steel", "milling_machine"], "desc": "Morse's fluted twist drill that cleared its own chips, the standard metal drilling tool."},
{"id": "pneumatic_tool", "name": "Pneumatic tool", "year": 1861, "cat": "manufacturing", "wiki": "Pneumatic tool", "req": ["steam_engine", "machine_tools"], "desc": "Tools driven by compressed air, first used for rock drilling in Alpine tunnels."},
{"id": "servomechanism", "name": "Servomechanism", "year": 1868, "cat": "manufacturing", "wiki": "Servomechanism", "req": ["centrifugal_governor"], "desc": "A feedback-controlled actuator; Farcot's steam steering engine gave the idea its name."},
{"id": "injection_molding", "name": "Injection molding", "year": 1872, "cat": "manufacturing", "wiki": "Injection moulding", "req": ["die_casting", "hydraulic_press", "celluloid"], "desc": "Injecting molten material into a mould, patented by the Hyatt brothers and central to plastics manufacturing."},
{"id": "screw_machine", "name": "Automatic screw machine", "year": 1873, "cat": "manufacturing", "wiki": "Automatic lathe", "req": ["turret_lathe", "cam"], "desc": "Spencer's cam-controlled automatic lathe that turned out screws and small parts unattended."},
{"id": "grinding_wheel", "name": "Grinding wheel", "year": 1873, "cat": "manufacturing", "wiki": "Grinding wheel", "req": ["machine_tools"], "desc": "A bonded abrasive wheel for cutting and finishing hard materials."},
{"id": "grinding_machine", "name": "Grinding machine", "year": 1876, "cat": "manufacturing", "wiki": "Grinding machine", "req": ["grinding_wheel", "lathe"], "desc": "A machine that finishes parts to fine tolerances with an abrasive wheel; Brown & Sharpe's universal grinder."},
{"id": "stamping", "name": "Metal stamping", "year": 1880, "cat": "manufacturing", "wiki": "Stamping (metalworking)", "req": ["hydraulic_press", "steel", "interchangeable_parts"], "desc": "Pressing sheet metal between dies to cut and form parts, used for bicycles and later car bodies."},
{"id": "roller_chain", "name": "Roller chain", "year": 1880, "cat": "manufacturing", "wiki": "Roller chain", "req": ["chain_drive", "steel", "gear"], "desc": "Renold's bushed roller chain, efficient power transmission for bicycles and machinery."},
{"id": "arc_welding", "name": "Arc welding", "year": 1881, "cat": "manufacturing", "wiki": "Arc welding", "req": ["electric_generator", "arc_lamp"], "desc": "Welding with heat from an electric arc, first done with carbon electrodes by Benardos."},
{"id": "resistance_welding", "name": "Resistance welding", "year": 1886, "cat": "manufacturing", "wiki": "Electric resistance welding", "req": ["transformer", "electric_generator"], "desc": "Joining metal by passing current through pressed-together parts, invented by Elihu Thomson."},
{"id": "time_and_motion_study", "name": "Time and motion study", "year": 1890, "cat": "manufacturing", "wiki": "Time and motion study", "req": ["factory_system"], "desc": "Measuring and analyzing work steps to set standard times and remove wasted motion."},
{"id": "conveyor_belt", "name": "Conveyor belt", "year": 1892, "cat": "manufacturing", "wiki": "Conveyor belt", "req": ["belt_drive", "vulcanization"], "desc": "A moving rubber or fabric belt that carries material continuously, first used widely in mining."},
{"id": "power_tool", "name": "Power tool", "year": 1895, "cat": "manufacturing", "wiki": "Power tool", "req": ["electric_motor"], "desc": "Hand-held tools driven by motors; Fein's 1895 portable electric drill was among the first."},
{"id": "tapered_roller_bearing", "name": "Tapered roller bearing", "year": 1898, "cat": "manufacturing", "wiki": "Tapered roller bearing", "req": ["ball_bearing"], "desc": "Timken's conical roller bearing that carries both radial and thrust loads."},
{"id": "oxy_fuel_welding", "name": "Oxy-fuel welding", "year": 1903, "cat": "manufacturing", "wiki": "Oxy–fuel welding and cutting", "req": ["modern_chemistry", "air_separation", "calcium_carbide"], "desc": "Welding and cutting with an oxygen-acetylene flame, introduced by Fouche and Picard."},
{"id": "smaw", "name": "Shielded metal arc welding", "year": 1907, "cat": "manufacturing", "wiki": "Shielded metal arc welding", "req": ["arc_welding"], "desc": "Arc welding with flux-coated electrodes, made practical by Kjellberg; still the most common manual process."},
{"id": "powder_metallurgy", "name": "Powder metallurgy", "year": 1909, "cat": "manufacturing", "wiki": "Powder metallurgy", "req": ["hydraulic_press", "modern_chemistry"], "desc": "Making parts by pressing and sintering metal powders, first industrialized for tungsten filaments."},
{"id": "scientific_management", "name": "Scientific management", "year": 1911, "cat": "manufacturing", "wiki": "Scientific management", "req": ["time_and_motion_study", "factory_system"], "desc": "Taylor's system of analyzing and standardizing work to raise productivity."},
{"id": "fordism", "name": "Fordism", "year": 1914, "cat": "manufacturing", "wiki": "Fordism", "req": ["assembly_line", "scientific_management"], "desc": "Ford's combination of moving assembly lines, standardized products and high wages."},
{"id": "forklift", "name": "Forklift", "year": 1917, "cat": "manufacturing", "wiki": "Forklift", "req": ["electric_motor", "automobile", "truck"], "desc": "A powered truck with lifting forks for moving loads in warehouses and factories."},
{"id": "jig_borer", "name": "Jig borer", "year": 1921, "cat": "manufacturing", "wiki": "Jig borer", "req": ["milling_machine", "boring_machine", "micrometer_gauge"], "desc": "A precision machine for locating and boring holes in jigs and dies to fine tolerances."},
{"id": "autonomation", "name": "Autonomation", "year": 1924, "cat": "manufacturing", "wiki": "Autonomation", "req": ["power_loom"], "desc": "Machines that stop themselves on detecting a defect, from Toyoda's automatic loom; a pillar of Toyota's system."},
{"id": "statistical_process_control", "name": "Statistical process control", "year": 1924, "cat": "manufacturing", "wiki": "Statistical process control", "req": ["mass_production", "statistics"], "desc": "Shewhart's use of control charts and statistics to monitor and stabilize manufacturing processes."},
{"id": "pallet", "name": "Pallet", "year": 1925, "cat": "manufacturing", "wiki": "Pallet", "req": ["forklift"], "desc": "A flat transport platform lifted by forklifts, standardizing the handling of unit loads."},
{"id": "chainsaw", "name": "Chainsaw", "year": 1926, "cat": "manufacturing", "wiki": "Chainsaw", "req": ["roller_chain", "internal_combustion_engine", "saw"], "desc": "A portable saw with cutting teeth on a driven chain, transforming logging."},
{"id": "submerged_arc_welding", "name": "Submerged arc welding", "year": 1935, "cat": "manufacturing", "wiki": "Submerged arc welding", "req": ["arc_welding"], "desc": "Automatic arc welding under a blanket of granular flux, used for heavy plate and pipes."},
{"id": "blow_molding", "name": "Blow molding", "year": 1938, "cat": "manufacturing", "wiki": "Blow molding", "req": ["extrusion", "bakelite"], "desc": "Inflating a hot plastic tube inside a mould to make hollow items such as bottles."},
{"id": "gtaw", "name": "TIG welding", "year": 1941, "cat": "manufacturing", "wiki": "Gas tungsten arc welding", "req": ["arc_welding"], "desc": "Arc welding with a non-consumable tungsten electrode under inert gas, developed for magnesium aircraft parts."},
{"id": "edm", "name": "Electrical discharge machining", "year": 1943, "cat": "manufacturing", "wiki": "Electrical discharge machining", "req": ["electromagnetism", "machine_tools"], "desc": "Eroding metal with controlled electric sparks, able to cut very hard materials and complex shapes."},
{"id": "gmaw", "name": "MIG welding", "year": 1948, "cat": "manufacturing", "wiki": "Gas metal arc welding", "req": ["arc_welding"], "desc": "Arc welding with a continuously fed wire electrode under shielding gas, fast and easy to automate."},
{"id": "toyota_production_system", "name": "Toyota Production System", "year": 1950, "cat": "manufacturing", "wiki": "Toyota Production System", "req": ["assembly_line", "autonomation", "scientific_management"], "desc": "Toyota's system of eliminating waste through just-in-time flow and built-in quality."},
{"id": "numerical_control", "name": "Numerical control", "year": 1952, "cat": "manufacturing", "wiki": "Computer numerical control", "req": ["milling_machine", "punched_card", "servomechanism", "electronic_computer"], "desc": "Automatic control of machine tools by coded instructions, first demonstrated at MIT."},
{"id": "automated_guided_vehicle", "name": "Automated guided vehicle", "year": 1953, "cat": "manufacturing", "wiki": "Automated guided vehicle", "req": ["forklift", "electric_motor"], "desc": "A driverless vehicle that follows wires or markers to move materials in factories."},
{"id": "kanban", "name": "Kanban", "year": 1953, "cat": "manufacturing", "wiki": "Kanban", "req": ["toyota_production_system"], "desc": "A card-based signaling system that pulls parts through production only as needed."},
{"id": "angle_grinder", "name": "Angle grinder", "year": 1954, "cat": "manufacturing", "wiki": "Angle grinder", "req": ["power_tool", "grinding_wheel"], "desc": "A hand-held grinder with a right-angle drive for cutting and grinding metal and stone."},
{"id": "apt_language", "name": "APT programming language", "year": 1956, "cat": "manufacturing", "wiki": "APT (programming language)", "req": ["numerical_control", "electronic_computer"], "desc": "A high-level language for generating tool paths for numerically controlled machines."},
{"id": "plasma_cutting", "name": "Plasma cutting", "year": 1957, "cat": "manufacturing", "wiki": "Plasma cutting", "req": ["gtaw"], "desc": "Cutting electrically conductive metals with a jet of hot plasma."},
{"id": "electron_beam_welding", "name": "Electron-beam welding", "year": 1958, "cat": "manufacturing", "wiki": "Electron-beam welding", "req": ["cathode_ray_tube", "vacuum_pump"], "desc": "Welding with a focused electron beam in vacuum, giving deep, narrow welds."},
{"id": "coordinate_measuring_machine", "name": "Coordinate-measuring machine", "year": 1959, "cat": "manufacturing", "wiki": "Coordinate-measuring machine", "req": ["numerical_control", "micrometer_gauge"], "desc": "A machine that measures part geometry by probing points in three dimensions."},
{"id": "just_in_time", "name": "Just-in-time manufacturing", "year": 1960, "cat": "manufacturing", "wiki": "Lean manufacturing", "req": ["toyota_production_system", "kanban"], "desc": "Producing and delivering parts only when needed, cutting inventory and exposing problems."},
{"id": "industrial_robot", "name": "Industrial robot", "year": 1961, "cat": "manufacturing", "wiki": "Industrial robot", "req": ["numerical_control", "servomechanism"], "desc": "A programmable multi-axis manipulator for welding, handling and assembly."},
{"id": "unimate", "name": "Unimate", "year": 1961, "cat": "manufacturing", "wiki": "Unimate", "req": ["industrial_robot"], "desc": "The first industrial robot, installed at a General Motors die-casting plant in 1961."},
{"id": "poka_yoke", "name": "Poka-yoke", "year": 1961, "cat": "manufacturing", "wiki": "Poka-yoke", "req": ["toyota_production_system"], "desc": "Simple mistake-proofing devices that prevent or flag assembly errors."},
{"id": "g_code", "name": "G-code", "year": 1963, "cat": "manufacturing", "wiki": "G-code", "req": ["numerical_control", "apt_language"], "desc": "The standard language of instructions for numerically controlled machine tools."},
{"id": "mrp", "name": "Material requirements planning", "year": 1964, "cat": "manufacturing", "wiki": "Material requirements planning", "req": ["electronic_computer", "mass_production"], "desc": "Computer-based planning of parts and materials needed to meet a production schedule."},
{"id": "laser_cutting", "name": "Laser cutting", "year": 1965, "cat": "manufacturing", "wiki": "Laser cutting", "req": ["laser", "numerical_control"], "desc": "Cutting material with a focused high-power laser beam, often CNC-controlled."},
{"id": "diamond_turning", "name": "Diamond turning", "year": 1966, "cat": "manufacturing", "wiki": "Diamond turning", "req": ["numerical_control", "lathe"], "desc": "Ultra-precision turning with single-crystal diamond tools for optical-quality surfaces."},
{"id": "laser_beam_welding", "name": "Laser beam welding", "year": 1967, "cat": "manufacturing", "wiki": "Laser beam welding", "req": ["laser"], "desc": "Welding with a concentrated laser beam, giving fast, narrow welds suitable for automation."},
{"id": "flexible_manufacturing_system", "name": "Flexible manufacturing system", "year": 1967, "cat": "manufacturing", "wiki": "Flexible manufacturing system", "req": ["numerical_control", "conveyor_belt", "electronic_computer"], "desc": "Computer-controlled groups of machines and handling systems that can switch between products."},
{"id": "plc", "name": "Programmable logic controller", "year": 1968, "cat": "manufacturing", "wiki": "Programmable logic controller", "req": ["electronic_computer", "integrated_circuit"], "desc": "A ruggedized computer replacing relay panels to control factory machines, first built for GM."},
{"id": "robot_welding", "name": "Robot welding", "year": 1969, "cat": "manufacturing", "wiki": "Robot welding", "req": ["industrial_robot", "resistance_welding"], "desc": "Automated spot and arc welding by robots, introduced on car body lines."},
{"id": "stanford_arm", "name": "Stanford arm", "year": 1969, "cat": "manufacturing", "wiki": "Stanford arm", "req": ["industrial_robot", "electric_motor"], "desc": "An all-electric, computer-controlled robot arm that shaped later robot designs."},
{"id": "smed", "name": "Single-minute exchange of die", "year": 1969, "cat": "manufacturing", "wiki": "Single-minute exchange of die", "req": ["toyota_production_system", "stamping"], "desc": "Shingo's methods for cutting changeover times, enabling small-batch production."},
{"id": "water_jet_cutter", "name": "Water jet cutter", "year": 1970, "cat": "manufacturing", "wiki": "Water jet cutter", "req": ["hydraulic_press", "numerical_control"], "desc": "Cutting materials with a very high-pressure jet of water, optionally with abrasive."},
{"id": "cam_manufacturing", "name": "Computer-aided manufacturing", "year": 1971, "cat": "manufacturing", "wiki": "Computer-aided manufacturing", "req": ["computer_aided_design", "numerical_control"], "desc": "Using software to generate machine tool paths directly from digital designs."},
{"id": "humanoid_robot", "name": "Humanoid robot", "year": 1973, "cat": "manufacturing", "wiki": "Humanoid robot", "req": ["industrial_robot", "electronic_computer"], "desc": "A robot with a human-like body; WABOT-1 was first, and 2020s models target factory work."},
{"id": "computer_integrated_manufacturing", "name": "Computer-integrated manufacturing", "year": 1973, "cat": "manufacturing", "wiki": "Computer-integrated manufacturing", "req": ["computer_aided_design", "flexible_manufacturing_system", "mrp"], "desc": "Linking design, planning and production through shared computer systems."},
{"id": "machine_vision", "name": "Machine vision", "year": 1980, "cat": "manufacturing", "wiki": "Machine vision", "req": ["electronic_computer", "television", "ccd"], "desc": "Camera-based automatic inspection and guidance of robots in production."},
{"id": "scara", "name": "SCARA robot", "year": 1981, "cat": "manufacturing", "wiki": "SCARA", "req": ["industrial_robot"], "desc": "A selective-compliance robot arm designed for fast, precise assembly."},
{"id": "3d_printing", "name": "3D printing", "year": 1981, "cat": "manufacturing", "wiki": "3D printing", "req": ["computer_aided_design", "laser", "numerical_control"], "desc": "Building objects layer by layer from digital models, first proposed by Hideo Kodama."},
{"id": "stereolithography", "name": "Stereolithography", "year": 1984, "cat": "manufacturing", "wiki": "Stereolithography", "req": ["3d_printing", "laser"], "desc": "Curing liquid photopolymer layer by layer with ultraviolet light, patented by Chuck Hull."},
{"id": "tqm", "name": "Total quality management", "year": 1985, "cat": "manufacturing", "wiki": "Total quality management", "req": ["statistical_process_control"], "desc": "An organization-wide approach to continuous quality improvement."},
{"id": "six_sigma", "name": "Six Sigma", "year": 1986, "cat": "manufacturing", "wiki": "Six Sigma", "req": ["statistical_process_control", "tqm"], "desc": "Motorola's data-driven method for reducing process variation and defects."},
{"id": "sls", "name": "Selective laser sintering", "year": 1987, "cat": "manufacturing", "wiki": "Selective laser sintering", "req": ["3d_printing", "laser", "powder_metallurgy"], "desc": "Fusing powdered material with a laser, layer by layer, to build parts."},
{"id": "iso_9000", "name": "ISO 9000", "year": 1987, "cat": "manufacturing", "wiki": "ISO 9000 family", "req": ["tqm"], "desc": "International standards for quality management systems."},
{"id": "fdm", "name": "Fused filament fabrication", "year": 1989, "cat": "manufacturing", "wiki": "Fused filament fabrication", "req": ["3d_printing", "extrusion"], "desc": "3D printing by extruding melted thermoplastic filament along a path; the most common printer type."},
{"id": "erp", "name": "Enterprise resource planning", "year": 1990, "cat": "manufacturing", "wiki": "Enterprise resource planning", "req": ["mrp", "personal_computer"], "desc": "Integrated software covering production, supply chain, finance and personnel."},
{"id": "friction_stir_welding", "name": "Friction stir welding", "year": 1991, "cat": "manufacturing", "wiki": "Friction stir welding", "req": ["milling_machine"], "desc": "Solid-state joining by a rotating tool that stirs softened metal, invented at TWI."},
{"id": "selective_laser_melting", "name": "Selective laser melting", "year": 1995, "cat": "manufacturing", "wiki": "Selective laser melting", "req": ["sls"], "desc": "Fully melting metal powder with a laser to print dense metal parts."},
{"id": "cobot", "name": "Collaborative robot", "year": 1996, "cat": "manufacturing", "wiki": "Cobot", "req": ["industrial_robot"], "desc": "A robot designed to work safely alongside people without guarding."},
{"id": "electron_beam_melting", "name": "Electron-beam melting", "year": 1997, "cat": "manufacturing", "wiki": "Electron-beam additive manufacturing", "req": ["electron_beam_welding", "selective_laser_melting"], "desc": "Metal 3D printing that melts powder or wire with an electron beam in vacuum."},
{"id": "digital_twin", "name": "Digital twin", "year": 2002, "cat": "manufacturing", "wiki": "Digital twin", "req": ["computer_aided_design", "numerical_control"], "desc": "A live digital model of a physical product or process, fed by sensor data."},
{"id": "reprap", "name": "RepRap", "year": 2005, "cat": "manufacturing", "wiki": "RepRap", "req": ["fdm"], "desc": "An open-source self-replicating 3D printer that launched low-cost desktop printing."},
{"id": "iiot", "name": "Industrial internet of things", "year": 2010, "cat": "manufacturing", "wiki": "Industrial internet of things", "req": ["internet", "plc"], "desc": "Networked sensors and machines that share data for monitoring and control in industry."},
{"id": "industry_4", "name": "Industry 4.0", "year": 2011, "cat": "manufacturing", "wiki": "Fourth Industrial Revolution", "req": ["iiot", "digital_twin", "industrial_robot"], "desc": "The vision of connected, data-driven smart factories, named in Germany in 2011."},
{"id": "generative_design", "name": "Generative design", "year": 2016, "cat": "manufacturing", "wiki": "Generative design", "req": ["computer_aided_design", "artificial_intelligence", "3d_printing"], "desc": "Software that searches many design options against goals and constraints, often for additive parts."},
{"id": "ochre_pigment", "name": "Ochre pigment", "year": -100000, "cat": "materials", "wiki": "Ochre", "req": ["stone_tools"], "desc": "Iron-oxide earth ground and mixed into paint, the oldest known processed pigment."},
{"id": "leather_tanning", "name": "Leather tanning", "year": -7000, "cat": "materials", "wiki": "Tanning (leather)", "req": ["domestication_of_animals"], "desc": "Treating hides with tannins or minerals to make durable, rot-resistant leather."},
{"id": "native_copper", "name": "Native copper working", "year": -9000, "cat": "materials", "wiki": "Native copper", "req": ["stone_tools"], "desc": "Hammering naturally occurring metallic copper into beads and tools, the first use of metal."},
{"id": "annealing", "name": "Annealing", "year": -7000, "cat": "materials", "wiki": "Annealing (materials science)", "req": ["native_copper", "control_of_fire"], "desc": "Heating work-hardened metal to restore its ductility so it can be shaped further."},
{"id": "lead_smelting", "name": "Lead smelting", "year": -6500, "cat": "materials", "wiki": "Lead smelting", "req": ["control_of_fire", "pottery"], "desc": "Reducing lead ore with fire, probably the first metal extracted from ore."},
{"id": "crucible", "name": "Crucible", "year": -5000, "cat": "materials", "wiki": "Crucible", "req": ["pottery", "kiln"], "desc": "Heat-resistant ceramic vessel for melting metals, essential to casting and later crucible steel."},
{"id": "goldsmithing", "name": "Gold working", "year": -4600, "cat": "materials", "wiki": "Goldsmith", "req": ["native_copper", "annealing"], "desc": "Hammering, casting and joining gold, seen in the Varna necropolis hoard."},
{"id": "arsenical_bronze", "name": "Arsenical bronze", "year": -4200, "cat": "materials", "wiki": "Arsenical bronze", "req": ["smelting"], "desc": "Copper alloyed with arsenic, the first widely used bronze before tin bronze."},
{"id": "bellows", "name": "Bellows", "year": -3000, "cat": "materials", "wiki": "Bellows", "req": ["smelting", "leather_tanning"], "desc": "Device forcing air into a furnace to raise its temperature for smelting and forging."},
{"id": "tin_smelting", "name": "Tin", "year": -3500, "cat": "materials", "wiki": "Tin", "req": ["smelting"], "desc": "Extraction of tin from cassiterite, the key alloying metal for tin bronze."},
{"id": "cupellation", "name": "Cupellation", "year": -3500, "cat": "materials", "wiki": "Cupellation", "req": ["lead_smelting"], "desc": "Refining silver and gold by oxidizing lead in a porous cupel, the basis of silver production."},
{"id": "gilding", "name": "Gilding", "year": -2600, "cat": "materials", "wiki": "Gilding", "req": ["goldsmithing"], "desc": "Applying thin layers of gold to surfaces, later by fire-gilding with mercury amalgam."},
{"id": "brass", "name": "Brass", "year": -500, "cat": "materials", "wiki": "Brass", "req": ["bronze", "smelting"], "desc": "Copper-zinc alloy made first by cementation with zinc ore, later from metallic zinc."},
{"id": "zinc_smelting", "name": "Zinc smelting", "year": 900, "cat": "materials", "wiki": "Zinc smelting", "req": ["smelting", "distillation"], "desc": "Distilling metallic zinc from ore in retorts, first done at scale at Zawar in India."},
{"id": "patio_process", "name": "Patio process", "year": 1554, "cat": "materials", "wiki": "Patio process", "req": ["cupellation"], "desc": "Mercury amalgamation of silver ore in New Spain, which drove colonial silver output."},
{"id": "egyptian_faience", "name": "Faience", "year": -4000, "cat": "materials", "wiki": "Egyptian faience", "req": ["kiln"], "desc": "Glazed quartz ceramic from Mesopotamia and Egypt, a precursor to true glass."},
{"id": "ceramic_glaze", "name": "Ceramic glaze", "year": -3000, "cat": "materials", "wiki": "Ceramic glaze", "req": ["egyptian_faience", "kiln"], "desc": "Glassy coating fused onto pottery to make it waterproof and decorative."},
{"id": "egyptian_blue", "name": "Egyptian blue", "year": -2600, "cat": "materials", "wiki": "Egyptian blue", "req": ["kiln", "egyptian_faience"], "desc": "Calcium copper silicate, the first synthetic pigment."},
{"id": "stoneware", "name": "Stoneware", "year": -1500, "cat": "materials", "wiki": "Stoneware", "req": ["kiln", "ceramic_glaze"], "desc": "Dense, vitrified pottery fired at high temperature, first made in China."},
{"id": "dragon_kiln", "name": "Dragon kiln", "year": -500, "cat": "materials", "wiki": "Dragon kiln", "req": ["kiln", "stoneware"], "desc": "Long sloping Chinese climbing kiln reaching the high temperatures needed for stoneware and porcelain."},
{"id": "porcelain", "name": "Porcelain", "year": 200, "cat": "materials", "wiki": "Porcelain", "req": ["stoneware", "dragon_kiln"], "desc": "Translucent, hard ceramic of kaolin fired above 1200 C, developed in Han China."},
{"id": "tin_glaze", "name": "Tin-glazed pottery", "year": 800, "cat": "materials", "wiki": "Tin-glazed pottery", "req": ["ceramic_glaze", "tin_smelting"], "desc": "Opaque white tin-oxide glaze from Abbasid Iraq, the basis of maiolica and delftware."},
{"id": "meissen_porcelain", "name": "European hard-paste porcelain", "year": 1710, "cat": "materials", "wiki": "Meissen porcelain", "req": ["porcelain"], "desc": "First European hard-paste porcelain, reverse engineered at Meissen in Saxony."},
{"id": "fire_brick", "name": "Fire brick", "year": 1822, "cat": "materials", "wiki": "Fire brick", "req": ["kiln"], "desc": "Refractory brick able to line furnaces, critical for high-temperature metallurgy."},
{"id": "glassblowing", "name": "Glassblowing", "year": -50, "cat": "materials", "wiki": "Glassblowing", "req": ["glass"], "desc": "Inflating molten glass on a blowpipe, which made glass vessels cheap and common."},
{"id": "crown_glass", "name": "Crown glass", "year": 1320, "cat": "materials", "wiki": "Crown glass (window)", "req": ["glassblowing"], "desc": "Window glass made by spinning a blown bubble into a flat disc."},
{"id": "murano_glass", "name": "Venetian cristallo", "year": 1450, "cat": "materials", "wiki": "Venetian glass", "req": ["glassblowing"], "desc": "Clear, colourless Venetian glass that set Europe's standard for fine glassware."},
{"id": "lead_glass", "name": "Lead crystal", "year": 1674, "cat": "materials", "wiki": "Lead glass", "req": ["glass", "lead_smelting"], "desc": "Ravenscroft's lead-oxide glass, brilliant and dense, later vital for optical flint glass."},
{"id": "tempered_glass", "name": "Tempered glass", "year": 1874, "cat": "materials", "wiki": "Tempered glass", "req": ["plate_glass"], "desc": "Glass toughened by rapid cooling of its surface, shattering into blunt pieces."},
{"id": "borosilicate_glass", "name": "Borosilicate glass", "year": 1893, "cat": "materials", "wiki": "Borosilicate glass", "req": ["glass", "modern_chemistry"], "desc": "Schott's low-expansion glass resistant to thermal shock, used for labware and cookware."},
{"id": "laminated_glass", "name": "Laminated glass", "year": 1903, "cat": "materials", "wiki": "Laminated glass", "req": ["plate_glass", "celluloid"], "desc": "Glass bonded to a plastic interlayer so it holds together when broken."},
{"id": "glass_fiber", "name": "Glass fiber", "year": 1932, "cat": "materials", "wiki": "Glass fiber", "req": ["glass"], "desc": "Fine glass filaments produced in bulk, used for insulation and composites."},
{"id": "glass_ceramic", "name": "Glass-ceramic", "year": 1953, "cat": "materials", "wiki": "Glass-ceramic", "req": ["glass", "borosilicate_glass"], "desc": "Glass crystallized under control into a tough ceramic, discovered by Stookey at Corning."},
{"id": "float_glass", "name": "Float glass", "year": 1959, "cat": "materials", "wiki": "Float glass", "req": ["plate_glass", "tin_smelting"], "desc": "Pilkington process floating molten glass on molten tin to make flat sheets cheaply."},
{"id": "chem_strengthened_glass", "name": "Chemically strengthened glass", "year": 1962, "cat": "materials", "wiki": "Chemically strengthened glass", "req": ["glass", "tempered_glass"], "desc": "Glass toughened by ion exchange that swaps sodium for larger potassium ions."},
{"id": "gorilla_glass", "name": "Gorilla Glass", "year": 2007, "cat": "materials", "wiki": "Gorilla Glass", "req": ["chem_strengthened_glass", "smartphone"], "desc": "Corning's ion-exchanged aluminosilicate cover glass used on most touchscreen phones."},
{"id": "synthetic_ruby", "name": "Verneuil process", "year": 1902, "cat": "materials", "wiki": "Verneuil method", "req": ["modern_chemistry"], "desc": "Flame fusion process making synthetic ruby and sapphire, the first commercial crystal growth."},
{"id": "bloomery", "name": "Bloomery", "year": -1200, "cat": "materials", "wiki": "Bloomery", "req": ["iron_working", "bellows"], "desc": "Furnace reducing iron ore below its melting point to a spongy bloom of iron and slag."},
{"id": "wrought_iron", "name": "Wrought iron", "year": -1200, "cat": "materials", "wiki": "Wrought iron", "req": ["bloomery"], "desc": "Low-carbon iron worked by hammering, the main structural iron until the 1860s."},
{"id": "quenching", "name": "Quenching", "year": -1100, "cat": "materials", "wiki": "Quenching", "req": ["iron_working"], "desc": "Rapid cooling of hot steel in water or oil to harden it."},
{"id": "tempering", "name": "Tempering", "year": -800, "cat": "materials", "wiki": "Tempering (metallurgy)", "req": ["quenching", "steel"], "desc": "Reheating hardened steel to trade some hardness for toughness."},
{"id": "pattern_welding", "name": "Pattern welding", "year": -200, "cat": "materials", "wiki": "Pattern welding", "req": ["forge_welding", "steel"], "desc": "Forge-welding twisted bars of iron and steel into tough, patterned blades."},
{"id": "crucible_steel", "name": "Crucible steel", "year": -400, "cat": "materials", "wiki": "Crucible steel", "req": ["steel", "crucible"], "desc": "Steel melted in sealed crucibles, giving uniform high-carbon steel."},
{"id": "wootz_steel", "name": "Wootz steel", "year": -300, "cat": "materials", "wiki": "Wootz steel", "req": ["crucible_steel"], "desc": "High-carbon crucible steel from South India, exported as ingots across Asia."},
{"id": "damascus_steel", "name": "Damascus steel", "year": 900, "cat": "materials", "wiki": "Damascus steel", "req": ["wootz_steel", "forge_welding"], "desc": "Blades forged from wootz ingots, famed for their watery pattern and sharpness."},
{"id": "finery_forge", "name": "Finery forge", "year": -200, "cat": "materials", "wiki": "Finery forge", "req": ["cast_iron"], "desc": "Decarburizing cast pig iron into wrought iron, first in Han China then medieval Europe."},
{"id": "tatara", "name": "Tatara furnace", "year": 600, "cat": "materials", "wiki": "Tatara (furnace)", "req": ["bloomery"], "desc": "Japanese clay bloomery producing tamahagane steel for swords."},
{"id": "cementation_process", "name": "Cementation process", "year": 1601, "cat": "materials", "wiki": "Cementation process", "req": ["wrought_iron", "steel"], "desc": "Packing wrought iron bars in charcoal to absorb carbon, producing blister steel."},
{"id": "reverberatory_furnace", "name": "Reverberatory furnace", "year": 1650, "cat": "materials", "wiki": "Reverberatory furnace", "req": ["kiln", "coal_mining"], "desc": "Furnace keeping fuel apart from the charge, allowing coal to be used for smelting."},
{"id": "tinplate", "name": "Tinplate", "year": 1720, "cat": "materials", "wiki": "Tinplate", "req": ["rolling_mill", "tin_smelting"], "desc": "Rolled iron sheet coated with tin, later the material of food cans."},
{"id": "huntsman_crucible", "name": "Huntsman crucible steel", "year": 1740, "cat": "materials", "wiki": "Benjamin Huntsman", "req": ["crucible_steel", "coke_fuel"], "desc": "Huntsman's Sheffield process of melting blister steel in crucibles for uniform tool steel."},
{"id": "puddling", "name": "Puddling", "year": 1784, "cat": "materials", "wiki": "Puddling (metallurgy)", "req": ["reverberatory_furnace", "finery_forge", "coke_fuel"], "desc": "Cort's process stirring molten pig iron in a coal-fired furnace to make wrought iron at scale."},
{"id": "hot_blast", "name": "Hot blast", "year": 1828, "cat": "materials", "wiki": "Hot blast", "req": ["blast_furnace", "coke_fuel"], "desc": "Neilson's preheated air blast that cut blast-furnace fuel use sharply."},
{"id": "ferroalloy", "name": "Ferroalloys", "year": 1860, "cat": "materials", "wiki": "Ferroalloy", "req": ["blast_furnace"], "desc": "Iron alloys of manganese, silicon or chromium added to control steel chemistry."},
{"id": "metallography", "name": "Metallography", "year": 1863, "cat": "materials", "wiki": "Metallography", "req": ["microscope", "steel"], "desc": "Sorby's microscopic study of polished, etched metal that founded physical metallurgy."},
{"id": "open_hearth", "name": "Open-hearth furnace", "year": 1865, "cat": "materials", "wiki": "Open-hearth furnace", "req": ["bessemer_process", "thermodynamics", "fire_brick", "reverberatory_furnace"], "desc": "Siemens–Martin regenerative furnace that made most of the world's steel until the 1960s."},
{"id": "tool_steel", "name": "Tool steel", "year": 1868, "cat": "materials", "wiki": "Tool steel", "req": ["crucible_steel", "ferroalloy"], "desc": "Mushet's self-hardening tungsten steel for cutting tools."},
{"id": "thomas_process", "name": "Basic Bessemer process", "year": 1877, "cat": "materials", "wiki": "Gilchrist–Thomas process", "req": ["bessemer_process", "fire_brick"], "desc": "Thomas and Gilchrist's basic lining that removed phosphorus, opening Europe's phosphoric ores."},
{"id": "mangalloy", "name": "Manganese steel", "year": 1882, "cat": "materials", "wiki": "Mangalloy", "req": ["ferroalloy", "bessemer_process"], "desc": "Hadfield's tough, work-hardening steel, the first true alloy steel."},
{"id": "high_speed_steel", "name": "High-speed steel", "year": 1898, "cat": "materials", "wiki": "High-speed steel", "req": ["tool_steel"], "desc": "Taylor and White's heat-treated tool steel that cut metal several times faster."},
{"id": "electric_arc_furnace", "name": "Electric arc furnace", "year": 1900, "cat": "materials", "wiki": "Electric arc furnace", "req": ["electric_generator", "steel"], "desc": "Héroult's furnace melting steel with electric arcs, now the main route for recycled steel."},
{"id": "electrical_steel", "name": "Electrical steel", "year": 1900, "cat": "materials", "wiki": "Electrical steel", "req": ["ferroalloy", "transformer"], "desc": "Silicon steel with low magnetic losses, used in transformer and motor cores."},
{"id": "induction_furnace", "name": "Induction furnace", "year": 1907, "cat": "materials", "wiki": "Induction furnace", "req": ["transformer", "electromagnetism"], "desc": "Furnace heating metal by induced currents, giving clean melts for alloys."},
{"id": "stainless_steel", "name": "Stainless steel", "year": 1913, "cat": "materials", "wiki": "Stainless steel", "req": ["ferroalloy", "electric_arc_furnace", "metallography"], "desc": "Chromium steel that resists rust, developed by Brearley and Krupp."},
{"id": "ductile_iron", "name": "Ductile iron", "year": 1943, "cat": "materials", "wiki": "Ductile iron", "req": ["cast_iron", "metallography"], "desc": "Cast iron with nodular graphite from magnesium additions, strong and tough."},
{"id": "air_separation", "name": "Air separation", "year": 1902, "cat": "materials", "wiki": "Air separation", "req": ["refrigeration", "hampson_linde_cycle", "liquefaction_of_gases"], "desc": "Linde's cryogenic distillation of air into oxygen and nitrogen on an industrial scale."},
{"id": "continuous_casting", "name": "Continuous casting", "year": 1950, "cat": "materials", "wiki": "Continuous casting", "req": ["steel", "metal_casting"], "desc": "Solidifying molten steel directly into slabs and billets, replacing ingot casting."},
{"id": "basic_oxygen", "name": "Basic oxygen steelmaking", "year": 1952, "cat": "materials", "wiki": "Basic oxygen steelmaking", "req": ["bessemer_process", "air_separation"], "desc": "Linz-Donawitz process blowing pure oxygen into pig iron, the dominant steelmaking route."},
{"id": "direct_reduced_iron", "name": "Direct reduced iron", "year": 1957, "cat": "materials", "wiki": "Direct reduced iron", "req": ["iron_working", "oil_refining"], "desc": "Reducing iron ore with natural-gas-derived gas below melting, bypassing the blast furnace."},
{"id": "hybrit", "name": "Hydrogen-based steelmaking", "year": 2021, "cat": "materials", "wiki": "Steelmaking", "req": ["direct_reduced_iron", "electrolysis", "electric_arc_furnace"], "desc": "Swedish fossil-free route reducing iron ore with green hydrogen, first delivered in 2021."},
{"id": "dislocation_theory", "name": "Dislocation theory", "year": 1934, "cat": "materials", "wiki": "Dislocation", "req": ["x_ray_crystallography", "metallography"], "desc": "Taylor, Orowan and Polanyi's explanation of plastic deformation by line defects in crystals."},
{"id": "electroplating", "name": "Electroplating", "year": 1805, "cat": "materials", "wiki": "Electroplating", "req": ["voltaic_pile", "electrolysis"], "desc": "Depositing a metal coating by electric current, first done by Brugnatelli."},
{"id": "galvanization", "name": "Hot-dip galvanization", "year": 1837, "cat": "materials", "wiki": "Hot-dip galvanization", "req": ["zinc_smelting", "wrought_iron"], "desc": "Coating iron with molten zinc to protect it from rust."},
{"id": "gold_cyanidation", "name": "Gold cyanidation", "year": 1887, "cat": "materials", "wiki": "Gold cyanidation", "req": ["modern_chemistry"], "desc": "Leaching gold from low-grade ore with cyanide, still the main gold extraction method."},
{"id": "bayer_process", "name": "Bayer process", "year": 1888, "cat": "materials", "wiki": "Bayer process", "req": ["modern_chemistry", "aluminium_smelting"], "desc": "Refining bauxite into alumina, the feedstock for aluminium smelting."},
{"id": "froth_flotation", "name": "Froth flotation", "year": 1905, "cat": "materials", "wiki": "Froth flotation", "req": ["modern_chemistry"], "desc": "Separating ore minerals by attaching them to air bubbles, enabling low-grade copper mining."},
{"id": "duralumin", "name": "Duralumin", "year": 1906, "cat": "materials", "wiki": "Duralumin", "req": ["aluminium_smelting", "metallography"], "desc": "Wilm's age-hardening aluminium-copper alloy, the structural metal of airships and aircraft."},
{"id": "tungsten", "name": "Ductile tungsten", "year": 1906, "cat": "materials", "wiki": "Tungsten", "req": ["light_bulb"], "desc": "Coolidge's process making tungsten drawable into wire, used for lamp filaments."},
{"id": "magnesium_alloy", "name": "Magnesium alloy", "year": 1908, "cat": "materials", "wiki": "Magnesium alloy", "req": ["electrolysis"], "desc": "Lightest structural metals, developed in Germany as Elektron alloys."},
{"id": "cemented_carbide", "name": "Cemented carbide", "year": 1926, "cat": "materials", "wiki": "Cemented carbide", "req": ["powder_metallurgy", "tungsten"], "desc": "Tungsten carbide bonded with cobalt, the standard material for cutting tools."},
{"id": "alnico", "name": "Alnico", "year": 1931, "cat": "materials", "wiki": "Alnico", "req": ["steel", "electromagnet"], "desc": "Aluminium-nickel-cobalt permanent magnet alloy, far stronger than magnet steel."},
{"id": "kroll_process", "name": "Kroll process", "year": 1940, "cat": "materials", "wiki": "Kroll process", "req": ["magnesium_alloy", "van_arkel_process"], "desc": "Reducing titanium tetrachloride with magnesium, the basis of all titanium production."},
{"id": "superalloy", "name": "Superalloy", "year": 1941, "cat": "materials", "wiki": "Superalloy", "req": ["stainless_steel", "jet_engine"], "desc": "Nickel-based alloys like Nimonic that keep their strength in jet engine turbines."},
{"id": "titanium_alloy", "name": "Titanium alloys", "year": 1954, "cat": "materials", "wiki": "Titanium alloys", "req": ["kroll_process", "vacuum_arc_remelting"], "desc": "Light, strong, corrosion-resistant alloys such as Ti-6Al-4V for aircraft and implants."},
{"id": "vacuum_arc_remelting", "name": "Vacuum arc remelting", "year": 1950, "cat": "materials", "wiki": "Vacuum arc remelting", "req": ["electric_arc_furnace", "vacuum_pump"], "desc": "Remelting reactive alloys under vacuum to remove gases and inclusions."},
{"id": "amorphous_metal", "name": "Metallic glass", "year": 1960, "cat": "materials", "wiki": "Amorphous metal", "req": ["quenching", "metallography"], "desc": "Metal alloys cooled so fast they solidify without crystal structure."},
{"id": "shape_memory_alloy", "name": "Shape-memory alloy", "year": 1962, "cat": "materials", "wiki": "Shape-memory alloy", "req": ["kroll_process"], "desc": "Alloys like Nitinol that return to a set shape when heated."},
{"id": "directional_solidification", "name": "Single-crystal turbine blades", "year": 1965, "cat": "materials", "wiki": "Directional solidification", "req": ["superalloy", "lost_wax_casting"], "desc": "Casting superalloy blades as columnar or single crystals to resist creep."},
{"id": "samarium_cobalt", "name": "Samarium–cobalt magnet", "year": 1966, "cat": "materials", "wiki": "Samarium–cobalt magnet", "req": ["alnico", "powder_metallurgy"], "desc": "First rare-earth permanent magnet, strong and stable at high temperature."},
{"id": "thermal_barrier_coating", "name": "Thermal barrier coating", "year": 1976, "cat": "materials", "wiki": "Thermal barrier coating", "req": ["superalloy", "fire_brick"], "desc": "Ceramic zirconia coatings letting turbine blades run above their melting point."},
{"id": "ndfeb_magnet", "name": "Neodymium magnet", "year": 1984, "cat": "materials", "wiki": "Neodymium magnet", "req": ["samarium_cobalt", "powder_metallurgy"], "desc": "NdFeB magnets, the strongest permanent magnets, used in motors, drives and wind turbines."},
{"id": "high_entropy_alloy", "name": "High-entropy alloy", "year": 2004, "cat": "materials", "wiki": "High-entropy alloy", "req": ["superalloy"], "desc": "Alloys of five or more elements in near-equal proportions with unusual properties."},
{"id": "indigo_dye", "name": "Indigo dye", "year": -4000, "cat": "materials", "wiki": "Indigo dye", "req": ["agriculture", "weaving"], "desc": "Blue dye from fermented Indigofera leaves, used from ancient Peru to India."},
{"id": "mordant", "name": "Mordant dyeing", "year": -2000, "cat": "materials", "wiki": "Mordant", "req": ["weaving"], "desc": "Fixing dyes to fibre with metal salts like alum, essential to madder and other dyes."},
{"id": "tyrian_purple", "name": "Tyrian purple", "year": -1570, "cat": "materials", "wiki": "Tyrian purple", "req": ["weaving", "mordant"], "desc": "Costly Phoenician dye from murex snails, a mark of royalty."},
{"id": "lead_white", "name": "Lead white", "year": -400, "cat": "materials", "wiki": "Lead white", "req": ["lead_smelting"], "desc": "Basic lead carbonate, the principal white paint pigment until the 20th century."},
{"id": "oil_paint", "name": "Oil paint", "year": 650, "cat": "materials", "wiki": "Oil paint", "req": ["ochre_pigment", "agriculture"], "desc": "Pigment bound in drying oil, used in Bamiyan and perfected in 15th-century Flanders."},
{"id": "nitric_acid", "name": "Nitric acid", "year": 1300, "cat": "materials", "wiki": "Nitric acid", "req": ["distillation"], "desc": "Aqua fortis made by distilling saltpetre with vitriol, used to part gold and silver."},
{"id": "prussian_blue", "name": "Prussian blue", "year": 1706, "cat": "materials", "wiki": "Prussian blue", "req": ["distillation", "iron_working"], "desc": "First modern synthetic pigment, discovered by accident in Berlin."},
{"id": "lead_chamber_process", "name": "Lead chamber process", "year": 1746, "cat": "materials", "wiki": "Lead chamber process", "req": ["lead_smelting", "distillation"], "desc": "Roebuck's large-scale sulfuric acid process in lead-lined chambers."},
{"id": "leblanc_process", "name": "Leblanc process", "year": 1791, "cat": "materials", "wiki": "Leblanc process", "req": ["lead_chamber_process", "modern_chemistry"], "desc": "Making soda ash from salt and sulfuric acid, the first heavy-chemical industry."},
{"id": "coal_tar", "name": "Coal tar", "year": 1820, "cat": "materials", "wiki": "Coal tar", "req": ["coke_fuel", "distillation"], "desc": "Byproduct of coal gas and coke making, the feedstock of the synthetic dye industry."},
{"id": "wohler_synthesis", "name": "Wöhler synthesis", "year": 1828, "cat": "materials", "wiki": "Wöhler synthesis", "req": ["modern_chemistry"], "desc": "Synthesis of urea from inorganic salts, launching organic synthesis."},
{"id": "catalysis", "name": "Catalysis", "year": 1835, "cat": "materials", "wiki": "Catalysis", "req": ["modern_chemistry"], "desc": "Berzelius's recognition that some substances speed reactions without being consumed."},
{"id": "mauveine", "name": "Mauveine", "year": 1856, "cat": "materials", "wiki": "Mauveine", "req": ["coal_tar", "wohler_synthesis"], "desc": "Perkin's aniline purple, the first commercial synthetic dye."},
{"id": "solvay_process", "name": "Solvay process", "year": 1861, "cat": "materials", "wiki": "Solvay process", "req": ["modern_chemistry"], "desc": "Ammonia-soda process that displaced Leblanc as the source of sodium carbonate."},
{"id": "azo_dye", "name": "Azo dyes", "year": 1861, "cat": "materials", "wiki": "Azo dye", "req": ["mauveine"], "desc": "Large family of synthetic dyes from diazo coupling, still the most used dye class."},
{"id": "alizarin", "name": "Synthetic alizarin", "year": 1869, "cat": "materials", "wiki": "Alizarin", "req": ["mauveine"], "desc": "Graebe and Liebermann's synthesis of madder red, which wiped out madder farming."},
{"id": "contact_process", "name": "Contact process", "year": 1875, "cat": "materials", "wiki": "Contact process", "req": ["lead_chamber_process", "catalysis"], "desc": "Catalytic oxidation of sulfur dioxide giving concentrated sulfuric acid."},
{"id": "synthetic_indigo", "name": "Synthetic indigo", "year": 1882, "cat": "materials", "wiki": "Baeyer–Drewsen indigo synthesis", "req": ["coal_tar", "indigo_dye"], "desc": "Laboratory synthesis of indigo that, via BASF in 1897, replaced natural indigo."},
{"id": "chloralkali", "name": "Chloralkali process", "year": 1892, "cat": "materials", "wiki": "Chloralkali process", "req": ["electrolysis", "electric_generator"], "desc": "Electrolysis of brine into chlorine and caustic soda, backbone of the chemical industry."},
{"id": "calcium_carbide", "name": "Calcium carbide", "year": 1892, "cat": "materials", "wiki": "Calcium carbide", "req": ["electric_generator", "kiln"], "desc": "Willson's electric-furnace product yielding acetylene for lighting and synthesis."},
{"id": "silicon_carbide", "name": "Silicon carbide", "year": 1891, "cat": "materials", "wiki": "Silicon carbide", "req": ["electric_generator"], "desc": "Acheson's carborundum, a hard synthetic abrasive and later a power semiconductor."},
{"id": "synthetic_graphite", "name": "Synthetic graphite", "year": 1896, "cat": "materials", "wiki": "Acheson process", "req": ["silicon_carbide"], "desc": "Acheson's electric-furnace graphite for electrodes and later nuclear moderators."},
{"id": "ostwald_process", "name": "Ostwald process", "year": 1902, "cat": "materials", "wiki": "Ostwald process", "req": ["catalysis", "nitric_acid"], "desc": "Catalytic oxidation of ammonia to nitric acid for fertilizer and explosives."},
{"id": "titanium_dioxide", "name": "Titanium dioxide pigment", "year": 1916, "cat": "materials", "wiki": "Titanium dioxide", "req": ["modern_chemistry", "contact_process"], "desc": "Bright, non-toxic white pigment that replaced lead white in paint."},
{"id": "cfc", "name": "Chlorofluorocarbons", "year": 1928, "cat": "materials", "wiki": "Chlorofluorocarbon", "req": ["refrigeration", "catalysis"], "desc": "Midgley's Freon refrigerants, later banned for destroying the ozone layer."},
{"id": "nitrocellulose", "name": "Nitrocellulose", "year": 1846, "cat": "materials", "wiki": "Nitrocellulose", "req": ["nitric_acid", "lead_chamber_process", "modern_chemistry"], "desc": "Schönbein's guncotton, a powerful explosive and the first semi-synthetic polymer."},
{"id": "nitroglycerin", "name": "Nitroglycerin", "year": 1847, "cat": "materials", "wiki": "Nitroglycerin", "req": ["nitric_acid", "lead_chamber_process"], "desc": "Sobrero's highly sensitive liquid explosive."},
{"id": "blasting_cap", "name": "Blasting cap", "year": 1865, "cat": "materials", "wiki": "Detonator", "req": ["nitroglycerin"], "desc": "Nobel's mercury fulminate detonator, making high explosives usable."},
{"id": "dynamite", "name": "Dynamite", "year": 1867, "cat": "materials", "wiki": "Dynamite", "req": ["nitroglycerin", "blasting_cap"], "desc": "Nobel's nitroglycerin absorbed in kieselguhr, safe enough for mining and tunnelling."},
{"id": "smokeless_powder", "name": "Smokeless powder", "year": 1884, "cat": "materials", "wiki": "Smokeless powder", "req": ["nitrocellulose", "gunpowder"], "desc": "Vieille's Poudre B propellant that replaced black powder in firearms."},
{"id": "picric_acid", "name": "Picric acid", "year": 1885, "cat": "materials", "wiki": "Picric acid", "req": ["coal_tar", "nitric_acid"], "desc": "Phenol-derived high explosive used as lyddite and melinite in shells."},
{"id": "cordite", "name": "Cordite", "year": 1889, "cat": "materials", "wiki": "Cordite", "req": ["nitroglycerin", "nitrocellulose"], "desc": "British double-base smokeless propellant."},
{"id": "tnt", "name": "TNT", "year": 1891, "cat": "materials", "wiki": "TNT", "req": ["coal_tar", "nitric_acid", "contact_process"], "desc": "Trinitrotoluene, a stable, meltable military explosive mass-produced from 1891."},
{"id": "rdx", "name": "RDX", "year": 1920, "cat": "materials", "wiki": "RDX", "req": ["nitric_acid"], "desc": "Cyclonite, a high-brisance explosive central to WWII munitions and plastic explosives."},
{"id": "plastic_explosive", "name": "Plastic explosive", "year": 1940, "cat": "materials", "wiki": "Plastic explosive", "req": ["rdx"], "desc": "Mouldable explosives such as Composition C based on RDX."},
{"id": "anfo", "name": "ANFO", "year": 1955, "cat": "materials", "wiki": "ANFO", "req": ["haber_process", "oil_refining"], "desc": "Ammonium nitrate and fuel oil, the cheap bulk explosive of modern mining."},
{"id": "natural_rubber", "name": "Natural rubber", "year": -1600, "cat": "materials", "wiki": "Natural rubber", "req": ["agriculture"], "desc": "Latex from rubber trees, processed by Mesoamericans to make balls and waterproofing."},
{"id": "gutta_percha", "name": "Gutta-percha", "year": 1843, "cat": "materials", "wiki": "Gutta-percha", "req": ["natural_rubber"], "desc": "Natural latex that insulated the first submarine telegraph cables."},
{"id": "celluloid", "name": "Celluloid", "year": 1856, "cat": "materials", "wiki": "Celluloid", "req": ["nitrocellulose"], "desc": "Nitrocellulose plastic first made as Parkesine in 1856, later camphor-plasticized celluloid for film and billiard balls."},
{"id": "rayon", "name": "Rayon", "year": 1891, "cat": "materials", "wiki": "Rayon", "req": ["nitrocellulose"], "desc": "Regenerated cellulose fibre, the first manufactured textile fibre."},
{"id": "cellophane", "name": "Cellophane", "year": 1908, "cat": "materials", "wiki": "Cellophane", "req": ["rayon"], "desc": "Transparent regenerated cellulose film, the first clear packaging film."},
{"id": "synthetic_rubber", "name": "Synthetic rubber", "year": 1909, "cat": "materials", "wiki": "Synthetic rubber", "req": ["natural_rubber", "coal_tar"], "desc": "Hofmann's methyl rubber and later Buna, made from small-molecule monomers."},
{"id": "macromolecule", "name": "Macromolecular theory", "year": 1920, "cat": "materials", "wiki": "Macromolecule", "req": ["modern_chemistry", "bakelite"], "desc": "Staudinger's proof that polymers are long covalent chains, founding polymer science."},
{"id": "steam_cracking", "name": "Steam cracking", "year": 1920, "cat": "materials", "wiki": "Steam cracking", "req": ["cracking"], "desc": "Cracking hydrocarbons with steam to produce ethylene and propylene, the plastics feedstock."},
{"id": "petrochemicals", "name": "Petrochemicals", "year": 1920, "cat": "materials", "wiki": "Petrochemical", "req": ["oil_refining", "steam_cracking"], "desc": "Chemicals made from petroleum and gas, starting with isopropanol in 1920."},
{"id": "pvc", "name": "PVC", "year": 1926, "cat": "materials", "wiki": "Polyvinyl chloride", "req": ["chloralkali", "calcium_carbide", "macromolecule"], "desc": "Semon's plasticized polyvinyl chloride, now the third most produced plastic."},
{"id": "neoprene", "name": "Neoprene", "year": 1930, "cat": "materials", "wiki": "Neoprene", "req": ["synthetic_rubber", "calcium_carbide"], "desc": "DuPont's oil-resistant polychloroprene, the first mass-produced synthetic rubber."},
{"id": "sbr", "name": "Styrene-butadiene rubber", "year": 1929, "cat": "materials", "wiki": "Styrene-butadiene", "req": ["synthetic_rubber"], "desc": "Buna S copolymer that became the main tyre rubber after WWII."},
{"id": "polystyrene", "name": "Polystyrene", "year": 1931, "cat": "materials", "wiki": "Polystyrene", "req": ["macromolecule", "petrochemicals"], "desc": "Rigid, clear plastic from IG Farben, later foamed as Styrofoam."},
{"id": "aerogel", "name": "Aerogel", "year": 1931, "cat": "materials", "wiki": "Aerogel", "req": ["modern_chemistry"], "desc": "Kistler's ultralight solid made by replacing a gel's liquid with gas."},
{"id": "polyethylene", "name": "Polyethylene", "year": 1933, "cat": "materials", "wiki": "Polyethylene", "req": ["macromolecule", "petrochemicals"], "desc": "ICI's high-pressure polymer of ethylene, crucial for radar cables and now the top plastic."},
{"id": "pmma", "name": "Acrylic glass", "year": 1933, "cat": "materials", "wiki": "Poly(methyl methacrylate)", "req": ["macromolecule"], "desc": "Plexiglas, a clear shatter-resistant substitute for glass."},
{"id": "nylon", "name": "Nylon", "year": 1935, "cat": "materials", "wiki": "Nylon", "req": ["macromolecule", "coal_tar"], "desc": "Carothers's polyamide, the first fully synthetic fibre."},
{"id": "epoxy", "name": "Epoxy", "year": 1936, "cat": "materials", "wiki": "Epoxy", "req": ["macromolecule"], "desc": "Thermosetting resins used as strong adhesives and composite matrices."},
{"id": "polyurethane", "name": "Polyurethane", "year": 1937, "cat": "materials", "wiki": "Polyurethane", "req": ["macromolecule"], "desc": "Bayer's versatile polymer used for foams, coatings and elastomers."},
{"id": "ptfe", "name": "PTFE", "year": 1938, "cat": "materials", "wiki": "Polytetrafluoroethylene", "req": ["cfc", "macromolecule"], "desc": "Plunkett's Teflon, chemically inert and extremely slippery."},
{"id": "silicone", "name": "Silicone", "year": 1940, "cat": "materials", "wiki": "Silicone", "req": ["macromolecule", "silicon_carbide"], "desc": "Silicon-oxygen polymers stable over wide temperatures, made via Rochow's direct process."},
{"id": "pet", "name": "Polyester (PET)", "year": 1941, "cat": "materials", "wiki": "Polyethylene terephthalate", "req": ["nylon", "petrochemicals"], "desc": "Whinfield and Dickson's polyester, used in fibres and later drink bottles."},
{"id": "acrylic_fiber", "name": "Acrylic fiber", "year": 1941, "cat": "materials", "wiki": "Acrylic fiber", "req": ["macromolecule", "petrochemicals"], "desc": "Polyacrylonitrile fibre, also the precursor for most carbon fibre."},
{"id": "fiberglass", "name": "Fiberglass", "year": 1942, "cat": "materials", "wiki": "Fiberglass", "req": ["glass_fiber", "bakelite"], "desc": "Glass-fibre-reinforced plastic used for boats, car bodies and panels."},
{"id": "zeolite", "name": "Synthetic zeolites", "year": 1948, "cat": "materials", "wiki": "Zeolite", "req": ["catalysis"], "desc": "Microporous aluminosilicates used as molecular sieves and cracking catalysts."},
{"id": "ziegler_natta", "name": "Ziegler–Natta catalyst", "year": 1953, "cat": "materials", "wiki": "Ziegler–Natta catalyst", "req": ["polyethylene", "catalysis"], "desc": "Catalysts polymerizing olefins at low pressure into linear, stereoregular chains."},
{"id": "polycarbonate", "name": "Polycarbonate", "year": 1953, "cat": "materials", "wiki": "Polycarbonate", "req": ["macromolecule", "petrochemicals"], "desc": "Tough transparent thermoplastic used for lenses, discs and glazing."},
{"id": "polypropylene", "name": "Polypropylene", "year": 1954, "cat": "materials", "wiki": "Polypropylene", "req": ["ziegler_natta"], "desc": "Natta's isotactic polymer, now the second most produced plastic."},
{"id": "kevlar", "name": "Kevlar", "year": 1965, "cat": "materials", "wiki": "Kevlar", "req": ["nylon", "liquid_crystal"], "desc": "Kwolek's para-aramid fibre, five times stronger than steel by weight."},
{"id": "uhmwpe_fiber", "name": "UHMWPE fiber", "year": 1979, "cat": "materials", "wiki": "Ultra-high-molecular-weight polyethylene", "req": ["ziegler_natta"], "desc": "Gel-spun polyethylene fibre (Dyneema), among the strongest fibres per weight."},
{"id": "conductive_polymer", "name": "Conductive polymer", "year": 1977, "cat": "materials", "wiki": "Conductive polymer", "req": ["macromolecule", "semiconductor"], "desc": "Doped polyacetylene showing metallic conductivity, enabling organic electronics."},
{"id": "pla", "name": "Polylactic acid", "year": 1994, "cat": "materials", "wiki": "Polylactic acid", "req": ["macromolecule", "agriculture"], "desc": "Bio-based, compostable polyester made from fermented plant sugar."},
{"id": "carbon_fiber", "name": "Carbon fiber", "year": 1963, "cat": "materials", "wiki": "Carbon fibers", "req": ["acrylic_fiber", "synthetic_graphite"], "desc": "Strong, stiff graphitic filaments, made from PAN at the RAE from 1963."},
{"id": "cfrp", "name": "Carbon-fiber-reinforced polymer", "year": 1968, "cat": "materials", "wiki": "Carbon fiber reinforced polymer", "req": ["carbon_fiber", "epoxy"], "desc": "Lightweight composite used in aircraft, racing cars and wind blades."},
{"id": "carbon_carbon", "name": "Reinforced carbon–carbon", "year": 1965, "cat": "materials", "wiki": "Reinforced carbon–carbon", "req": ["carbon_fiber"], "desc": "Carbon fibre in a graphite matrix, used on Space Shuttle leading edges and brakes."},
{"id": "ceramic_matrix_composite", "name": "Ceramic matrix composite", "year": 1975, "cat": "materials", "wiki": "Ceramic matrix composite", "req": ["silicon_carbide", "carbon_fiber"], "desc": "Fibre-toughened ceramics now used in hot sections of jet engines."},
{"id": "synthetic_diamond", "name": "Synthetic diamond", "year": 1954, "cat": "materials", "wiki": "Synthetic diamond", "req": ["synthetic_graphite", "catalysis"], "desc": "GE's high-pressure, high-temperature diamond, used as an industrial abrasive."},
{"id": "fullerene", "name": "Fullerene", "year": 1985, "cat": "materials", "wiki": "Fullerene", "req": ["laser", "synthetic_graphite", "mass_spectrometry"], "desc": "Buckminsterfullerene C60, a new form of carbon found in laser-vaporized graphite."},
{"id": "carbon_nanotube", "name": "Carbon nanotube", "year": 1991, "cat": "materials", "wiki": "Carbon nanotube", "req": ["fullerene", "transmission_electron_microscopy"], "desc": "Rolled graphene cylinders with extreme strength and conductivity, reported by Iijima."},
{"id": "graphene", "name": "Graphene", "year": 2004, "cat": "materials", "wiki": "Graphene", "req": ["synthetic_graphite", "carbon_nanotube"], "desc": "Single atomic layer of carbon isolated by Geim and Novoselov."},
{"id": "twistronics", "name": "Twisted bilayer graphene", "year": 2018, "cat": "materials", "wiki": "Twistronics", "req": ["graphene", "superconductivity"], "desc": "Graphene layers at a magic angle, showing superconductivity and correlated states."},
{"id": "cyanobiphenyl", "name": "Cyanobiphenyl liquid crystals", "year": 1972, "cat": "materials", "wiki": "4-Cyano-4'-pentylbiphenyl", "req": ["liquid_crystal"], "desc": "Gray's stable room-temperature liquid crystals that made LCDs practical."},
{"id": "niobium_titanium", "name": "Niobium–titanium", "year": 1962, "cat": "materials", "wiki": "Niobium–titanium", "req": ["superconductivity", "kroll_process"], "desc": "Ductile superconducting alloy used in MRI magnets and particle accelerators."},
{"id": "high_tc", "name": "High-temperature superconductivity", "year": 1986, "cat": "materials", "wiki": "High-temperature superconductivity", "req": ["superconductivity", "perovskite_oxides"], "desc": "Bednorz and Müller's cuprate superconductors, operating far above previous limits."},
{"id": "ybco", "name": "YBCO", "year": 1987, "cat": "materials", "wiki": "Yttrium barium copper oxide", "req": ["high_tc"], "desc": "First superconductor working above liquid nitrogen temperature."},
{"id": "iron_superconductor", "name": "Iron-based superconductor", "year": 2008, "cat": "materials", "wiki": "Iron-based superconductor", "req": ["high_tc"], "desc": "Second family of high-temperature superconductors, based on iron pnictides."},
{"id": "perovskite_oxides", "name": "Barium titanate", "year": 1941, "cat": "materials", "wiki": "Barium titanate", "req": ["x_ray_crystallography", "kiln"], "desc": "Ferroelectric perovskite ceramic, the basis of ceramic capacitors and piezo devices."},
{"id": "pzt", "name": "Lead zirconate titanate", "year": 1952, "cat": "materials", "wiki": "Lead zirconate titanate", "req": ["perovskite_oxides"], "desc": "PZT piezoelectric ceramic used in sensors, actuators and ultrasound."},
{"id": "monocrystalline_silicon", "name": "Monocrystalline silicon", "year": 1954, "cat": "materials", "wiki": "Monocrystalline silicon", "req": ["czochralski_method", "zone_melting"], "desc": "Single-crystal silicon of electronic grade, the substrate of modern chips."},
{"id": "polysilicon", "name": "Polysilicon (Siemens process)", "year": 1957, "cat": "materials", "wiki": "Polycrystalline silicon", "req": ["chloralkali", "semiconductor"], "desc": "Ultrapure silicon deposited from trichlorosilane, feedstock for wafers and solar cells."},
{"id": "gallium_arsenide", "name": "Gallium arsenide", "year": 1952, "cat": "materials", "wiki": "Gallium arsenide", "req": ["semiconductor"], "desc": "III-V compound semiconductor for fast transistors, LEDs, lasers and space solar cells."},
{"id": "indium_tin_oxide", "name": "Indium tin oxide", "year": 1954, "cat": "materials", "wiki": "Indium tin oxide", "req": ["tin_smelting", "semiconductor"], "desc": "Transparent conductor used in touchscreens and flat-panel displays."},
{"id": "mocvd", "name": "Metalorganic vapour-phase epitaxy", "year": 1968, "cat": "materials", "wiki": "Metalorganic vapour-phase epitaxy", "req": ["gallium_arsenide", "catalysis", "epitaxy"], "desc": "Chemical vapour growth of compound semiconductor layers for LEDs and lasers."},
{"id": "gallium_nitride", "name": "Gallium nitride", "year": 1986, "cat": "materials", "wiki": "Gallium nitride", "req": ["mocvd"], "desc": "Wide-bandgap semiconductor whose high-quality growth enabled blue LEDs."},
{"id": "photonic_crystal", "name": "Photonic crystal", "year": 1987, "cat": "materials", "wiki": "Photonic crystal", "req": ["maxwell_equations", "semiconductor"], "desc": "Periodic structures that control light much as crystals control electrons."},
{"id": "metamaterial", "name": "Metamaterial", "year": 2000, "cat": "materials", "wiki": "Metamaterial", "req": ["photonic_crystal", "photolithography"], "desc": "Engineered structures with properties absent in nature, such as negative refraction."},
{"id": "topological_insulator", "name": "Topological insulator", "year": 2007, "cat": "materials", "wiki": "Topological insulator", "req": ["quantum_mechanics", "molecular_beam_epitaxy"], "desc": "Materials insulating inside but conducting on their surface, protected by topology."},
{"id": "nanotechnology", "name": "Nanotechnology", "year": 1981, "cat": "materials", "wiki": "Nanotechnology", "req": ["quantum_mechanics", "photolithography"], "desc": "Engineering matter at the 1 to 100 nanometre scale."},
{"id": "mof", "name": "Metal–organic framework", "year": 1999, "cat": "materials", "wiki": "Metal–organic framework", "req": ["zeolite", "catalysis"], "desc": "Porous crystalline frameworks of metal nodes and organic linkers for gas storage and capture."},
{"id": "tin_trade", "name": "Ancient tin trade", "year": -2500, "cat": "materials", "wiki": "Tin sources and trade during antiquity", "req": ["tin_smelting", "sail"], "desc": "Long-distance trade moving scarce tin from Cornwall, Iberia and Central Asia to bronze makers."},
{"id": "repousse", "name": "Repoussé and chasing", "year": -2500, "cat": "materials", "wiki": "Repoussé and chasing", "req": ["goldsmithing"], "desc": "Hammering sheet metal from behind and in front to create relief decoration."},
{"id": "granulation", "name": "Granulation", "year": -2500, "cat": "materials", "wiki": "Granulation (jewellery)", "req": ["goldsmithing"], "desc": "Decorating gold with tiny fused spheres, a hallmark of Sumerian and Etruscan jewelry."},
{"id": "filigree", "name": "Filigree", "year": -2500, "cat": "materials", "wiki": "Filigree", "req": ["goldsmithing"], "desc": "Jewelry of fine twisted gold or silver wire soldered into lacelike patterns."},
{"id": "pewter", "name": "Pewter", "year": -1450, "cat": "materials", "wiki": "Pewter", "req": ["tin_smelting", "lead_smelting"], "desc": "Tin-based alloy used for tableware and vessels from ancient Egypt to the 19th century."},
{"id": "lacquer", "name": "Lacquer", "year": -7000, "cat": "materials", "wiki": "Lacquer", "req": ["stone_tools"], "desc": "Hard protective coating from the sap of the lacquer tree, used in East Asia since the Jomon period."},
{"id": "lustreware", "name": "Lustreware", "year": 800, "cat": "materials", "wiki": "Lustreware", "req": ["tin_glaze"], "desc": "Pottery with a metallic sheen from silver and copper nanoparticles in the glaze, from Abbasid Iraq."},
{"id": "bone_china", "name": "Bone china", "year": 1748, "cat": "materials", "wiki": "Bone china", "req": ["porcelain"], "desc": "English porcelain containing bone ash, strong and white, perfected by Spode around 1800."},
{"id": "jasperware", "name": "Jasperware", "year": 1775, "cat": "materials", "wiki": "Jasperware", "req": ["stoneware"], "desc": "Wedgwood's unglazed coloured stoneware, a product of systematic ceramic experiments."},
{"id": "stained_glass", "name": "Stained glass", "year": 650, "cat": "materials", "wiki": "Stained glass", "req": ["glass"], "desc": "Coloured glass pieces set in lead cames, used for church windows from the early Middle Ages."},
{"id": "fused_quartz", "name": "Fused quartz", "year": 1900, "cat": "materials", "wiki": "Fused quartz", "req": ["glass"], "desc": "Pure silica glass with very low thermal expansion and high UV transparency."},
{"id": "bioglass", "name": "Bioactive glass", "year": 1969, "cat": "materials", "wiki": "Bioglass 45S5", "req": ["glass"], "desc": "Hench's glass that bonds to bone, the first bioactive material."},
{"id": "case_hardening", "name": "Case-hardening", "year": -1000, "cat": "materials", "wiki": "Case-hardening", "req": ["wrought_iron"], "desc": "Adding carbon to the surface of iron to give it a hard steel skin."},
{"id": "malleable_iron", "name": "Malleable iron", "year": 1722, "cat": "materials", "wiki": "Malleable iron", "req": ["cast_iron"], "desc": "Cast iron made ductile by long annealing, described by Réaumur."},
{"id": "babbitt_metal", "name": "Babbitt metal", "year": 1839, "cat": "materials", "wiki": "Babbitt (alloy)", "req": ["tin_smelting"], "desc": "Tin- or lead-based bearing alloy that made high-speed machinery bearings practical."},
{"id": "invar", "name": "Invar", "year": 1896, "cat": "materials", "wiki": "Invar", "req": ["steel", "ferroalloy"], "desc": "Guillaume's nickel-iron alloy with almost no thermal expansion, for precision instruments."},
{"id": "monel", "name": "Monel", "year": 1905, "cat": "materials", "wiki": "Monel", "req": ["mond_process"], "desc": "Corrosion-resistant nickel-copper alloy used in marine and chemical equipment."},
{"id": "nichrome", "name": "Nichrome", "year": 1906, "cat": "materials", "wiki": "Nichrome", "req": ["ferroalloy", "electric_generator"], "desc": "Marsh's nickel-chromium resistance alloy, enabling electric heaters and toasters."},
{"id": "stellite", "name": "Stellite", "year": 1907, "cat": "materials", "wiki": "Stellite", "req": ["ferroalloy"], "desc": "Haynes's hard, wear-resistant cobalt-chromium alloy."},
{"id": "permalloy", "name": "Permalloy", "year": 1914, "cat": "materials", "wiki": "Permalloy", "req": ["electrical_steel", "telegraph"], "desc": "Nickel-iron alloy of very high magnetic permeability, used to load submarine cables."},
{"id": "weathering_steel", "name": "Weathering steel", "year": 1933, "cat": "materials", "wiki": "Weathering steel", "req": ["steel", "ferroalloy"], "desc": "Cor-Ten steel forming a stable rust layer that removes the need for paint."},
{"id": "electroslag_remelting", "name": "Electroslag remelting", "year": 1940, "cat": "materials", "wiki": "Electro-slag remelting", "req": ["electric_arc_furnace"], "desc": "Refining steel and superalloy ingots by remelting through molten slag."},
{"id": "maraging_steel", "name": "Maraging steel", "year": 1960, "cat": "materials", "wiki": "Maraging steel", "req": ["ferroalloy", "metallography"], "desc": "Ultra-high-strength nickel steel hardened by precipitation rather than carbon."},
{"id": "cathodic_protection", "name": "Cathodic protection", "year": 1824, "cat": "materials", "wiki": "Cathodic protection", "req": ["voltaic_pile"], "desc": "Davy's method of stopping corrosion by making a metal the cathode of a cell."},
{"id": "mond_process", "name": "Mond process", "year": 1890, "cat": "materials", "wiki": "Mond process", "req": ["modern_chemistry", "catalysis"], "desc": "Purifying nickel via volatile nickel carbonyl."},
{"id": "anodizing", "name": "Anodizing", "year": 1923, "cat": "materials", "wiki": "Anodizing", "req": ["aluminium_smelting", "electrolysis"], "desc": "Growing a protective oxide layer on aluminium electrochemically."},
{"id": "van_arkel_process", "name": "Crystal bar process", "year": 1925, "cat": "materials", "wiki": "Van Arkel–de Boer process", "req": ["modern_chemistry", "vacuum_pump"], "desc": "Iodide process yielding ultrapure titanium and zirconium."},
{"id": "zircaloy", "name": "Zircaloy", "year": 1952, "cat": "materials", "wiki": "Zirconium alloys", "req": ["van_arkel_process", "nuclear_reactor"], "desc": "Zirconium alloy cladding for nuclear fuel, nearly transparent to neutrons."},
{"id": "al_li_alloy", "name": "Aluminium–lithium alloy", "year": 1958, "cat": "materials", "wiki": "Aluminium–lithium alloys", "req": ["duralumin"], "desc": "Lighter, stiffer aluminium alloys for aircraft and rocket tanks."},
{"id": "metal_foam", "name": "Metal foam", "year": 1956, "cat": "materials", "wiki": "Metal foam", "req": ["aluminium_smelting"], "desc": "Cellular metals that are light and absorb impact energy."},
{"id": "ferrofluid", "name": "Ferrofluid", "year": 1963, "cat": "materials", "wiki": "Ferrofluid", "req": ["ferrite"], "desc": "Colloid of magnetic nanoparticles in a liquid, developed at NASA."},
{"id": "bismuth_telluride", "name": "Bismuth telluride", "year": 1954, "cat": "materials", "wiki": "Bismuth telluride", "req": ["semiconductor", "thermoelectric_effect"], "desc": "Thermoelectric semiconductor used in Peltier coolers and generators."},
{"id": "quasicrystal", "name": "Quasicrystal", "year": 1982, "cat": "materials", "wiki": "Quasicrystal", "req": ["x_ray_crystallography", "amorphous_metal"], "desc": "Shechtman's ordered but non-periodic crystals, overturning crystallography's rules."},
{"id": "birkeland_eyde", "name": "Birkeland–Eyde process", "year": 1903, "cat": "materials", "wiki": "Birkeland–Eyde process", "req": ["electric_generator", "nitric_acid"], "desc": "Electric-arc fixation of atmospheric nitrogen, superseded by Haber–Bosch."},
{"id": "tetraethyllead", "name": "Tetraethyllead", "year": 1921, "cat": "materials", "wiki": "Tetraethyllead", "req": ["petrochemicals", "lead_smelting"], "desc": "Anti-knock gasoline additive that raised engine compression, later banned for lead poisoning."},
{"id": "petn", "name": "PETN", "year": 1912, "cat": "materials", "wiki": "Pentaerythritol tetranitrate", "req": ["nitric_acid"], "desc": "Powerful explosive used in detonating cord and boosters."},
{"id": "ebonite", "name": "Ebonite", "year": 1851, "cat": "materials", "wiki": "Ebonite", "req": ["vulcanization"], "desc": "Hard rubber made by heavy vulcanization, an early moulded insulating material."},
{"id": "galalith", "name": "Galalith", "year": 1897, "cat": "materials", "wiki": "Galalith", "req": ["modern_chemistry"], "desc": "Casein-formaldehyde plastic used for buttons and jewelry."},
{"id": "cellulose_acetate", "name": "Cellulose acetate", "year": 1904, "cat": "materials", "wiki": "Cellulose acetate", "req": ["celluloid"], "desc": "Less flammable cellulose plastic used for safety film and fibres."},
{"id": "pvdc", "name": "Polyvinylidene chloride", "year": 1933, "cat": "materials", "wiki": "Polyvinylidene chloride", "req": ["chloralkali", "macromolecule"], "desc": "Saran, a barrier plastic used for food wrap and coatings."},
{"id": "acrylic_paint", "name": "Acrylic paint", "year": 1934, "cat": "materials", "wiki": "Acrylic paint", "req": ["pmma"], "desc": "Fast-drying paint with acrylic polymer binder."},
{"id": "ion_exchange_resin", "name": "Ion-exchange resin", "year": 1935, "cat": "materials", "wiki": "Ion-exchange resin", "req": ["macromolecule", "bakelite"], "desc": "Synthetic resins exchanging ions, used for water softening and rare-earth separation."},
{"id": "melamine_resin", "name": "Melamine resin", "year": 1936, "cat": "materials", "wiki": "Melamine resin", "req": ["macromolecule"], "desc": "Hard thermoset used in laminates such as Formica and tableware."},
{"id": "butyl_rubber", "name": "Butyl rubber", "year": 1937, "cat": "materials", "wiki": "Butyl rubber", "req": ["synthetic_rubber", "petrochemicals"], "desc": "Gas-tight synthetic rubber used in inner tubes and tyre liners."},
{"id": "cyanoacrylate", "name": "Cyanoacrylate", "year": 1942, "cat": "materials", "wiki": "Cyanoacrylate", "req": ["macromolecule"], "desc": "Instant-setting superglue discovered by Coover."},
{"id": "spandex", "name": "Spandex", "year": 1958, "cat": "materials", "wiki": "Spandex", "req": ["polyurethane"], "desc": "Highly elastic segmented polyurethane fibre."},
{"id": "hydrogel", "name": "Hydrogel", "year": 1960, "cat": "materials", "wiki": "Hydrogel", "req": ["macromolecule"], "desc": "Water-swollen polymer networks, first used by Wichterle for soft contact lenses."},
{"id": "nomex", "name": "Nomex", "year": 1961, "cat": "materials", "wiki": "Nomex", "req": ["nylon"], "desc": "Flame-resistant meta-aramid fibre."},
{"id": "nafion", "name": "Nafion", "year": 1962, "cat": "materials", "wiki": "Nafion", "req": ["ptfe"], "desc": "Sulfonated fluoropolymer membrane used in fuel cells and chlor-alkali cells."},
{"id": "polyimide", "name": "Kapton", "year": 1965, "cat": "materials", "wiki": "Kapton", "req": ["macromolecule"], "desc": "DuPont's heat-resistant polyimide film, used in flexible circuits and spacecraft."},
{"id": "superabsorbent", "name": "Superabsorbent polymer", "year": 1966, "cat": "materials", "wiki": "Superabsorbent polymer", "req": ["macromolecule"], "desc": "Polymers absorbing hundreds of times their weight in water, used in diapers."},
{"id": "peek", "name": "PEEK", "year": 1978, "cat": "materials", "wiki": "Polyether ether ketone", "req": ["macromolecule"], "desc": "High-performance thermoplastic for aerospace and medical implants."},
{"id": "kaminsky_catalyst", "name": "Metallocene catalyst", "year": 1980, "cat": "materials", "wiki": "Kaminsky catalyst", "req": ["ziegler_natta"], "desc": "Single-site metallocene catalysts giving precise control of polyolefins."},
{"id": "shape_memory_polymer", "name": "Shape-memory polymer", "year": 1984, "cat": "materials", "wiki": "Shape-memory polymer", "req": ["shape_memory_alloy", "polyurethane"], "desc": "Polymers that recover a programmed shape when heated."},
{"id": "self_healing", "name": "Self-healing material", "year": 2001, "cat": "materials", "wiki": "Self-healing material", "req": ["epoxy"], "desc": "Materials that repair damage on their own, such as White's microcapsule epoxy."},
{"id": "cubic_boron_nitride", "name": "Cubic boron nitride", "year": 1957, "cat": "materials", "wiki": "Boron nitride", "req": ["synthetic_diamond"], "desc": "Second-hardest material, used to machine hardened steels."},
{"id": "niobium_tin", "name": "Niobium–tin", "year": 1954, "cat": "materials", "wiki": "Niobium–tin", "req": ["superconductivity"], "desc": "Nb3Sn superconductor able to carry high currents in strong magnetic fields."},
{"id": "mgb2", "name": "Magnesium diboride", "year": 2001, "cat": "materials", "wiki": "Magnesium diboride", "req": ["superconductivity"], "desc": "Simple, cheap superconductor at 39 K."},
{"id": "amorphous_silicon", "name": "Amorphous silicon", "year": 1975, "cat": "materials", "wiki": "Amorphous silicon", "req": ["polysilicon", "chemical_vapor_deposition"], "desc": "Non-crystalline silicon that could be doped, used in thin-film transistors and solar cells."},
{"id": "colloidal_gold", "name": "Colloidal gold", "year": 1857, "cat": "materials", "wiki": "Colloidal gold", "req": ["goldsmithing", "modern_chemistry"], "desc": "Faraday's ruby gold sols, the first studied nanoparticles."},
{"id": "nanocellulose", "name": "Nanocellulose", "year": 1983, "cat": "materials", "wiki": "Nanocellulose", "req": ["nanotechnology"], "desc": "Cellulose fibrils and crystals at the nanoscale, strong and renewable."},
{"id": "mxene", "name": "MXenes", "year": 2011, "cat": "materials", "wiki": "MXenes", "req": ["graphene"], "desc": "Two-dimensional transition-metal carbides and nitrides made by etching MAX phases."},
{"id": "trepanning", "name": "Trepanning", "year": -7000, "cat": "medicine", "wiki": "Trepanning", "req": ["stone_tools"], "desc": "Drilling or scraping a hole in the skull, the oldest known surgical procedure, with many survivors showing healed bone."},
{"id": "dentistry", "name": "Dentistry", "year": -7000, "cat": "medicine", "wiki": "Dentistry", "req": ["stone_tools"], "desc": "Treating teeth, first attested by bow-drilled molars at Neolithic Mehrgarh."},
{"id": "herbalism", "name": "Herbal medicine", "year": -3000, "cat": "medicine", "wiki": "Herbal medicine", "req": ["agriculture"], "desc": "Systematic use of plants as remedies, recorded on Sumerian tablets and the basis of most early pharmacology."},
{"id": "opium", "name": "Opium", "year": -3400, "cat": "medicine", "wiki": "Opium", "req": ["agriculture"], "desc": "Dried poppy latex used since antiquity to relieve pain and induce sleep."},
{"id": "surgical_suture", "name": "Surgical suture", "year": -3000, "cat": "medicine", "wiki": "Surgical suture", "req": ["cordage", "sewing_needle"], "desc": "Stitching wounds closed with thread, practiced in ancient Egypt and India."},
{"id": "cauterization", "name": "Cauterization", "year": -3000, "cat": "medicine", "wiki": "Cauterization", "req": ["control_of_fire"], "desc": "Burning tissue with hot metal to stop bleeding and close wounds."},
{"id": "edwin_smith_papyrus", "name": "Edwin Smith Papyrus", "year": -1600, "cat": "medicine", "wiki": "Edwin Smith Papyrus", "req": ["papyrus"], "desc": "An Egyptian surgical treatise describing wounds and fractures with rational diagnosis and treatment."},
{"id": "ebers_papyrus", "name": "Ebers Papyrus", "year": -1550, "cat": "medicine", "wiki": "Ebers Papyrus", "req": ["papyrus", "herbalism"], "desc": "An Egyptian medical text listing hundreds of remedies and prescriptions."},
{"id": "prosthesis", "name": "Prosthesis", "year": -950, "cat": "medicine", "wiki": "Prosthesis", "req": ["stone_tools"], "desc": "Artificial body parts, from the wooden Cairo toe of ancient Egypt onward."},
{"id": "dentures", "name": "Dentures", "year": -700, "cat": "medicine", "wiki": "Dentures", "req": ["dentistry", "smelting"], "desc": "Removable replacement teeth, first made by the Etruscans with gold bands."},
{"id": "ayurveda", "name": "Ayurveda", "year": -600, "cat": "medicine", "wiki": "Ayurveda", "req": ["herbalism", "writing"], "desc": "The classical Indian medical system codified in the Charaka and Sushruta texts."},
{"id": "sushruta_samhita", "name": "Sushruta Samhita", "year": -600, "cat": "medicine", "wiki": "Sushruta Samhita", "req": ["ayurveda"], "desc": "An Indian surgical text describing over 300 procedures, including nasal reconstruction."},
{"id": "cataract_surgery", "name": "Cataract surgery", "year": -600, "cat": "medicine", "wiki": "Cataract surgery", "req": ["sushruta_samhita"], "desc": "Removing or displacing a clouded lens to restore sight, first by couching."},
{"id": "hippocratic_corpus", "name": "Hippocratic medicine", "year": -400, "cat": "medicine", "wiki": "Hippocratic Corpus", "req": ["writing"], "desc": "Greek texts treating disease as natural rather than divine and stressing observation and prognosis."},
{"id": "huangdi_neijing", "name": "Huangdi Neijing", "year": -200, "cat": "medicine", "wiki": "Huangdi Neijing", "req": ["herbalism", "writing"], "desc": "The foundational text of traditional Chinese medicine."},
{"id": "de_materia_medica", "name": "De materia medica", "year": 60, "cat": "medicine", "wiki": "De materia medica", "req": ["herbalism", "writing"], "desc": "Dioscorides' pharmacopoeia of about 600 plants, the standard drug reference for 1,500 years."},
{"id": "bimaristan", "name": "Bimaristan", "year": 805, "cat": "medicine", "wiki": "Bimaristan", "req": ["hippocratic_corpus"], "desc": "Hospitals of the medieval Islamic world, with wards, pharmacies and medical teaching."},
{"id": "canon_of_medicine", "name": "Canon of Medicine", "year": 1025, "cat": "medicine", "wiki": "The Canon of Medicine", "req": ["hippocratic_corpus", "paper"], "desc": "Avicenna's medical encyclopedia, a standard text in Europe and the Islamic world for centuries."},
{"id": "quarantine", "name": "Quarantine", "year": 1377, "cat": "medicine", "wiki": "Quarantine", "req": ["hippocratic_corpus"], "desc": "Isolating arrivals to stop the spread of plague, first decreed in Ragusa."},
{"id": "pharmacopoeia", "name": "Pharmacopoeia", "year": 1498, "cat": "medicine", "wiki": "Pharmacopoeia", "req": ["de_materia_medica", "printing_press"], "desc": "An official book standardizing drug preparations, beginning with the Florence Ricettario."},
{"id": "variolation", "name": "Variolation", "year": 1500, "cat": "medicine", "wiki": "Variolation", "req": ["huangdi_neijing"], "desc": "Deliberate infection with mild smallpox material to confer immunity, practiced in China, India and Africa."},
{"id": "de_fabrica", "name": "De humani corporis fabrica", "year": 1543, "cat": "medicine", "wiki": "De Humani Corporis Fabrica Libri Septem", "req": ["printing_press", "hippocratic_corpus"], "desc": "Vesalius' illustrated anatomy based on dissection, founding modern anatomy."},
{"id": "ligature", "name": "Surgical ligature", "year": 1552, "cat": "medicine", "wiki": "Ligature (medicine)", "req": ["surgical_suture"], "desc": "Tying off blood vessels during amputation, popularized by Ambroise Pare in place of cautery."},
{"id": "wheelchair", "name": "Wheelchair", "year": 1595, "cat": "medicine", "wiki": "Wheelchair", "req": ["wheel"], "desc": "A chair on wheels for people unable to walk, built for Philip II of Spain."},
{"id": "obstetric_forceps", "name": "Obstetric forceps", "year": 1600, "cat": "medicine", "wiki": "Obstetrical forceps", "req": ["steel"], "desc": "Hinged blades for assisting difficult births, invented by the Chamberlen family."},
{"id": "de_motu_cordis", "name": "Circulation of the blood", "year": 1628, "cat": "medicine", "wiki": "Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus", "req": ["de_fabrica", "scientific_method"], "desc": "William Harvey's proof that the heart pumps blood around a closed circuit."},
{"id": "clinical_trial", "name": "Clinical trial", "year": 1747, "cat": "medicine", "wiki": "Clinical trial", "req": ["scientific_method"], "desc": "Comparing treatments on groups of patients, as in James Lind's scurvy trial."},
{"id": "digitalis", "name": "Digitalis", "year": 1785, "cat": "medicine", "wiki": "Digoxin", "req": ["herbalism"], "desc": "Withering's foxglove extract for dropsy; its glycoside digoxin still treats heart failure."},
{"id": "ambulance", "name": "Ambulance", "year": 1792, "cat": "medicine", "wiki": "Ambulance", "req": ["cart"], "desc": "Dedicated vehicles carrying casualties to care, begun by Larrey's flying ambulances."},
{"id": "morphine", "name": "Morphine", "year": 1804, "cat": "medicine", "wiki": "Morphine", "req": ["opium", "modern_chemistry"], "desc": "The first alkaloid isolated from a plant, giving a pure, dosable painkiller."},
{"id": "endoscopy", "name": "Endoscopy", "year": 1806, "cat": "medicine", "wiki": "Endoscopy", "req": ["lens"], "desc": "Viewing inside body cavities through an instrument, begun with Bozzini's Lichtleiter."},
{"id": "stethoscope", "name": "Stethoscope", "year": 1816, "cat": "medicine", "wiki": "Stethoscope", "req": ["de_motu_cordis"], "desc": "Laennec's tube for listening to the heart and lungs, founding auscultation."},
{"id": "blood_transfusion", "name": "Blood transfusion", "year": 1818, "cat": "medicine", "wiki": "Blood transfusion", "req": ["de_motu_cordis"], "desc": "Transferring blood between people, first done human to human by James Blundell."},
{"id": "dental_braces", "name": "Dental braces", "year": 1819, "cat": "medicine", "wiki": "Dental braces", "req": ["dentistry"], "desc": "Wire appliances that gradually straighten teeth, the core of orthodontics."},
{"id": "quinine", "name": "Quinine", "year": 1820, "cat": "medicine", "wiki": "Quinine", "req": ["herbalism", "modern_chemistry"], "desc": "The antimalarial alkaloid isolated from cinchona bark, the first effective malaria drug."},
{"id": "dental_amalgam", "name": "Dental amalgam", "year": 1826, "cat": "medicine", "wiki": "Amalgam (dentistry)", "req": ["dentistry", "modern_chemistry"], "desc": "A mercury alloy filling that made durable dental restorations cheap."},
{"id": "iv_therapy", "name": "Intravenous therapy", "year": 1832, "cat": "medicine", "wiki": "Intravenous therapy", "req": ["de_motu_cordis"], "desc": "Infusing fluids into a vein, first used by Thomas Latta to treat cholera."},
{"id": "salicylic_acid", "name": "Salicylic acid", "year": 1838, "cat": "medicine", "wiki": "Salicylic acid", "req": ["herbalism", "modern_chemistry"], "desc": "The fever and pain reducer derived from willow bark, precursor of aspirin."},
{"id": "hand_washing", "name": "Hand washing", "year": 1847, "cat": "medicine", "wiki": "Hand washing", "req": ["clinical_trial"], "desc": "Semmelweis showed that washing hands in chlorine solution cut childbed fever deaths."},
{"id": "ophthalmoscope", "name": "Ophthalmoscope", "year": 1851, "cat": "medicine", "wiki": "Ophthalmoscopy", "req": ["lens"], "desc": "Helmholtz's instrument for viewing the retina in the living eye."},
{"id": "hypodermic_needle", "name": "Hypodermic syringe", "year": 1853, "cat": "medicine", "wiki": "Hypodermic needle", "req": ["steel", "glass"], "desc": "A hollow needle and syringe for injecting drugs under the skin."},
{"id": "broad_street_cholera", "name": "Epidemiological mapping", "year": 1854, "cat": "medicine", "wiki": "1854 Broad Street cholera outbreak", "req": ["scientific_method"], "desc": "John Snow traced cholera to a water pump, founding modern epidemiology."},
{"id": "antiseptic", "name": "Antiseptic surgery", "year": 1867, "cat": "medicine", "wiki": "Antiseptic", "req": ["germ_theory"], "desc": "Lister's use of carbolic acid to kill germs in wounds, sharply cutting surgical deaths."},
{"id": "clinical_thermometer", "name": "Clinical thermometer", "year": 1867, "cat": "medicine", "wiki": "Medical thermometer", "req": ["glass", "scientific_method", "thermometer"], "desc": "Allbutt's short, fast-reading mercury thermometer that made fever measurement routine."},
{"id": "attenuated_vaccine", "name": "Attenuated vaccine", "year": 1879, "cat": "medicine", "wiki": "Attenuated vaccine", "req": ["vaccination", "germ_theory"], "desc": "Pasteur's weakened chicken cholera culture, the first laboratory-made live vaccine."},
{"id": "cystoscopy", "name": "Cystoscope", "year": 1879, "cat": "medicine", "wiki": "Cystoscopy", "req": ["endoscopy", "light_bulb"], "desc": "Nitze's illuminated scope for the bladder, the first practical endoscope."},
{"id": "tracheal_intubation", "name": "Tracheal intubation", "year": 1880, "cat": "medicine", "wiki": "Tracheal intubation", "req": ["anesthesia"], "desc": "Passing a tube into the windpipe to secure the airway during anesthesia."},
{"id": "sphygmomanometer", "name": "Sphygmomanometer", "year": 1881, "cat": "medicine", "wiki": "Sphygmomanometer", "req": ["de_motu_cordis", "glass"], "desc": "A cuff and gauge for measuring blood pressure, refined by Riva-Rocci in 1896."},
{"id": "local_anesthesia", "name": "Local anesthesia", "year": 1884, "cat": "medicine", "wiki": "Local anesthesia", "req": ["anesthesia", "modern_chemistry"], "desc": "Koller's use of cocaine to numb the eye, allowing surgery on a conscious patient."},
{"id": "rabies_vaccine", "name": "Rabies vaccine", "year": 1885, "cat": "medicine", "wiki": "Rabies vaccine", "req": ["attenuated_vaccine"], "desc": "Pasteur's vaccine from dried infected spinal cord, the first against a human virus disease."},
{"id": "contact_lens", "name": "Contact lens", "year": 1888, "cat": "medicine", "wiki": "Contact lens", "req": ["lens", "glass"], "desc": "A lens worn on the eye's surface, first made of blown glass."},
{"id": "medical_glove", "name": "Surgical gloves", "year": 1889, "cat": "medicine", "wiki": "Medical glove", "req": ["vulcanization", "antiseptic"], "desc": "Thin rubber gloves worn in surgery, introduced by William Halsted."},
{"id": "asepsis", "name": "Aseptic technique", "year": 1890, "cat": "medicine", "wiki": "Asepsis", "req": ["antiseptic", "autoclave"], "desc": "Keeping germs out of the operating field through sterilized instruments, gowns and drapes."},
{"id": "diphtheria_antitoxin", "name": "Diphtheria antitoxin", "year": 1890, "cat": "medicine", "wiki": "Diphtheria antitoxin", "req": ["germ_theory"], "desc": "Behring and Kitasato's serum therapy, neutralizing a bacterial toxin with animal antibodies."},
{"id": "paracetamol", "name": "Paracetamol", "year": 1893, "cat": "medicine", "wiki": "Paracetamol", "req": ["modern_chemistry"], "desc": "A pain and fever reliever, also called acetaminophen, first used clinically in 1893."},
{"id": "internal_fixation", "name": "Internal fixation", "year": 1895, "cat": "medicine", "wiki": "Internal fixation", "req": ["asepsis", "steel"], "desc": "Repairing fractures with metal plates and screws, pioneered by Arbuthnot Lane."},
{"id": "inactivated_vaccine", "name": "Inactivated vaccine", "year": 1896, "cat": "medicine", "wiki": "Inactivated vaccine", "req": ["vaccination", "germ_theory"], "desc": "Vaccines from killed microbes, beginning with typhoid and cholera vaccines in 1896."},
{"id": "radiation_therapy", "name": "Radiation therapy", "year": 1896, "cat": "medicine", "wiki": "Radiation therapy", "req": ["x_ray"], "desc": "Using ionizing radiation to destroy tumors, tried within a year of X-rays' discovery."},
{"id": "fluoroscopy", "name": "Fluoroscopy", "year": 1896, "cat": "medicine", "wiki": "Fluoroscopy", "req": ["x_ray"], "desc": "Real-time X-ray imaging on a fluorescent screen."},
{"id": "aspirin", "name": "Aspirin", "year": 1897, "cat": "medicine", "wiki": "Aspirin", "req": ["salicylic_acid"], "desc": "Acetylsalicylic acid, synthesized at Bayer, a pain reliever later used to prevent heart attacks."},
{"id": "spinal_anaesthesia", "name": "Spinal anaesthesia", "year": 1898, "cat": "medicine", "wiki": "Spinal anaesthesia", "req": ["local_anesthesia", "hypodermic_needle"], "desc": "Injecting anesthetic into the spinal fluid to numb the lower body."},
{"id": "hearing_aid", "name": "Electric hearing aid", "year": 1898, "cat": "medicine", "wiki": "Hearing aid", "req": ["telephone"], "desc": "An amplifying device for the hard of hearing, first built from telephone parts."},
{"id": "abo_blood_group", "name": "ABO blood typing", "year": 1901, "cat": "medicine", "wiki": "ABO blood group system", "req": ["blood_transfusion", "microscope"], "desc": "Landsteiner's discovery of blood groups, making transfusion safe."},
{"id": "adrenaline", "name": "Adrenaline", "year": 1901, "cat": "medicine", "wiki": "Adrenaline", "req": ["modern_chemistry"], "desc": "The first hormone isolated, used for shock, asthma and severe allergy."},
{"id": "vascular_surgery", "name": "Vascular anastomosis", "year": 1902, "cat": "medicine", "wiki": "Vascular surgery", "req": ["surgical_suture", "asepsis"], "desc": "Carrel's technique for suturing blood vessels end to end, enabling transplants."},
{"id": "ecg", "name": "Electrocardiography", "year": 1903, "cat": "medicine", "wiki": "Electrocardiography", "req": ["electromagnetism", "de_motu_cordis"], "desc": "Recording the heart's electrical activity, made practical by Einthoven's string galvanometer."},
{"id": "iud", "name": "Intrauterine device", "year": 1909, "cat": "medicine", "wiki": "Intrauterine device", "req": ["asepsis"], "desc": "A small device placed in the uterus for long-acting contraception."},
{"id": "arsphenamine", "name": "Salvarsan", "year": 1910, "cat": "medicine", "wiki": "Arsphenamine", "req": ["germ_theory", "modern_chemistry"], "desc": "Ehrlich's arsenical cure for syphilis, the first modern synthetic chemotherapeutic drug."},
{"id": "laparoscopy", "name": "Laparoscopy", "year": 1910, "cat": "medicine", "wiki": "Laparoscopy", "req": ["cystoscopy"], "desc": "Examining the abdomen through a small incision with a scope, first done by Jacobaeus."},
{"id": "mammography", "name": "Mammography", "year": 1913, "cat": "medicine", "wiki": "Mammography", "req": ["x_ray"], "desc": "X-ray imaging of the breast to detect cancer early."},
{"id": "arthroscopy", "name": "Arthroscopy", "year": 1918, "cat": "medicine", "wiki": "Arthroscopy", "req": ["endoscopy", "cystoscopy"], "desc": "Looking inside joints through a small scope, now a routine way to repair them."},
{"id": "phage_therapy", "name": "Phage therapy", "year": 1919, "cat": "medicine", "wiki": "Phage therapy", "req": ["germ_theory", "bacteriophage"], "desc": "Treating bacterial infections with viruses that kill bacteria, revived against resistant strains."},
{"id": "microsurgery", "name": "Microsurgery", "year": 1921, "cat": "medicine", "wiki": "Microsurgery", "req": ["microscope"], "desc": "Surgery under an operating microscope, used for ear, eye and vessel repair."},
{"id": "bcg_vaccine", "name": "BCG vaccine", "year": 1921, "cat": "medicine", "wiki": "BCG vaccine", "req": ["attenuated_vaccine"], "desc": "An attenuated bovine bacillus vaccine against tuberculosis."},
{"id": "insulin", "name": "Insulin therapy", "year": 1922, "cat": "medicine", "wiki": "Insulin (medication)", "req": ["modern_chemistry", "hypodermic_needle"], "desc": "Banting and Best's pancreatic extract that turned type 1 diabetes from fatal to manageable."},
{"id": "toxoid", "name": "Toxoid vaccine", "year": 1923, "cat": "medicine", "wiki": "Toxoid", "req": ["diphtheria_antitoxin"], "desc": "Vaccines made from inactivated bacterial toxins, used against diphtheria and tetanus."},
{"id": "eeg", "name": "Electroencephalography", "year": 1924, "cat": "medicine", "wiki": "Electroencephalography", "req": ["ecg"], "desc": "Hans Berger's recording of the brain's electrical rhythms from the scalp."},
{"id": "angiography", "name": "Angiography", "year": 1927, "cat": "medicine", "wiki": "Angiography", "req": ["x_ray"], "desc": "X-ray imaging of blood vessels using injected contrast, introduced by Egas Moniz."},
{"id": "iron_lung", "name": "Iron lung", "year": 1928, "cat": "medicine", "wiki": "Iron lung", "req": ["electric_motor"], "desc": "A negative-pressure ventilator that kept paralyzed polio patients breathing."},
{"id": "cardiac_catheterization", "name": "Cardiac catheterization", "year": 1929, "cat": "medicine", "wiki": "Cardiac catheterization", "req": ["x_ray"], "desc": "Threading a catheter into the heart, first done by Forssmann on himself."},
{"id": "chloroquine", "name": "Chloroquine", "year": 1934, "cat": "medicine", "wiki": "Chloroquine", "req": ["quinine"], "desc": "A synthetic antimalarial that replaced quinine for decades."},
{"id": "sulfonamide", "name": "Sulfonamides", "year": 1935, "cat": "medicine", "wiki": "Sulfonamide (medicine)", "req": ["arsphenamine"], "desc": "Prontosil and its successors, the first broadly effective antibacterial drugs."},
{"id": "heparin", "name": "Heparin", "year": 1935, "cat": "medicine", "wiki": "Heparin", "req": ["modern_chemistry"], "desc": "An injectable anticoagulant that made dialysis and heart surgery possible."},
{"id": "blood_bank", "name": "Blood bank", "year": 1937, "cat": "medicine", "wiki": "Blood bank", "req": ["abo_blood_group", "refrigeration"], "desc": "Storing donated, typed and anticoagulated blood for later transfusion."},
{"id": "yellow_fever_vaccine", "name": "Yellow fever vaccine", "year": 1937, "cat": "medicine", "wiki": "Yellow fever vaccine", "req": ["attenuated_vaccine", "cell_culture"], "desc": "Theiler's 17D live vaccine, among the most effective ever made."},
{"id": "chemotherapy", "name": "Chemotherapy", "year": 1942, "cat": "medicine", "wiki": "Chemotherapy", "req": ["modern_chemistry"], "desc": "Treating cancer with cytotoxic drugs, starting with nitrogen mustard for lymphoma."},
{"id": "medical_ultrasound", "name": "Medical ultrasound", "year": 1942, "cat": "medicine", "wiki": "Medical ultrasound", "req": ["cathode_ray_tube", "vacuum_tube", "radar", "sonar"], "desc": "Imaging the body with reflected sound, applied to obstetrics by Ian Donald in 1958."},
{"id": "antihistamine", "name": "Antihistamines", "year": 1942, "cat": "medicine", "wiki": "Antihistamine", "req": ["modern_chemistry"], "desc": "Drugs blocking histamine to treat allergy, the first being phenbenzamine."},
{"id": "hemodialysis", "name": "Hemodialysis", "year": 1943, "cat": "medicine", "wiki": "Hemodialysis", "req": ["heparin"], "desc": "Kolff's artificial kidney, filtering blood through a membrane outside the body."},
{"id": "streptomycin", "name": "Streptomycin", "year": 1943, "cat": "medicine", "wiki": "Streptomycin", "req": ["penicillin"], "desc": "An antibiotic from soil bacteria, the first effective against tuberculosis."},
{"id": "influenza_vaccine", "name": "Influenza vaccine", "year": 1945, "cat": "medicine", "wiki": "Influenza vaccine", "req": ["inactivated_vaccine"], "desc": "Egg-grown inactivated flu vaccines, now updated yearly for circulating strains."},
{"id": "defibrillation", "name": "Defibrillator", "year": 1947, "cat": "medicine", "wiki": "Defibrillation", "req": ["ecg", "transformer"], "desc": "Delivering an electric shock to restore a normal heartbeat, first done in surgery by Claude Beck."},
{"id": "methotrexate", "name": "Methotrexate", "year": 1947, "cat": "medicine", "wiki": "Methotrexate", "req": ["chemotherapy"], "desc": "An antifolate that produced the first remissions in childhood leukemia."},
{"id": "stereotactic_surgery", "name": "Stereotactic surgery", "year": 1947, "cat": "medicine", "wiki": "Stereotactic surgery", "req": ["x_ray"], "desc": "Guiding instruments to precise brain targets using a 3D coordinate frame."},
{"id": "rct", "name": "Randomized controlled trial", "year": 1948, "cat": "medicine", "wiki": "Randomized controlled trial", "req": ["clinical_trial", "streptomycin"], "desc": "Assigning treatments at random, first done in the MRC streptomycin trial."},
{"id": "tetracycline", "name": "Tetracyclines", "year": 1948, "cat": "medicine", "wiki": "Tetracycline antibiotics", "req": ["streptomycin"], "desc": "A broad-spectrum antibiotic family from Streptomyces, starting with chlortetracycline."},
{"id": "cephalosporin", "name": "Cephalosporins", "year": 1948, "cat": "medicine", "wiki": "Cephalosporin", "req": ["penicillin"], "desc": "Beta-lactam antibiotics from a Sardinian mold, now in five generations."},
{"id": "cortisone", "name": "Cortisone", "year": 1948, "cat": "medicine", "wiki": "Cortisone", "req": ["modern_chemistry"], "desc": "The first corticosteroid used as a drug, dramatically relieving rheumatoid arthritis."},
{"id": "dpt_vaccine", "name": "DPT vaccine", "year": 1948, "cat": "medicine", "wiki": "DPT vaccine", "req": ["toxoid", "inactivated_vaccine"], "desc": "A combined vaccine against diphtheria, pertussis and tetanus."},
{"id": "lithium_medication", "name": "Lithium therapy", "year": 1949, "cat": "medicine", "wiki": "Lithium (medication)", "req": ["modern_chemistry"], "desc": "Cade's discovery that lithium salts stabilize bipolar disorder, the first mood stabilizer."},
{"id": "intraocular_lens", "name": "Intraocular lens", "year": 1949, "cat": "medicine", "wiki": "Intraocular lens", "req": ["cataract_surgery", "bakelite"], "desc": "Ridley's plastic lens implanted after cataract removal to restore focus."},
{"id": "cobalt_therapy", "name": "Cobalt therapy", "year": 1951, "cat": "medicine", "wiki": "Cobalt therapy", "req": ["radiation_therapy", "nuclear_reactor"], "desc": "Teletherapy with reactor-made cobalt-60, delivering deep, high-energy radiation to tumors."},
{"id": "norethisterone", "name": "Norethisterone", "year": 1951, "cat": "medicine", "wiki": "Norethisterone", "req": ["modern_chemistry"], "desc": "An orally active synthetic progestin, the key ingredient of the first birth control pills."},
{"id": "artificial_heart_valve", "name": "Artificial heart valve", "year": 1952, "cat": "medicine", "wiki": "Artificial heart valve", "req": ["bakelite"], "desc": "A mechanical valve implant, first a caged ball placed by Hufnagel."},
{"id": "isoniazid", "name": "Isoniazid", "year": 1952, "cat": "medicine", "wiki": "Isoniazid", "req": ["modern_chemistry", "streptomycin"], "desc": "A cheap oral tuberculosis drug that, combined with others, made TB curable."},
{"id": "chlorpromazine", "name": "Chlorpromazine", "year": 1952, "cat": "medicine", "wiki": "Chlorpromazine", "req": ["antihistamine"], "desc": "The first antipsychotic, which emptied asylums and began modern psychopharmacology."},
{"id": "mechanical_ventilation", "name": "Positive-pressure ventilation", "year": 1952, "cat": "medicine", "wiki": "Mechanical ventilation", "req": ["iron_lung", "tracheal_intubation"], "desc": "Pushing air into the lungs through a tube, adopted during the Copenhagen polio epidemic."},
{"id": "osseointegration", "name": "Osseointegration", "year": 1952, "cat": "medicine", "wiki": "Osseointegration", "req": ["internal_fixation"], "desc": "Branemark's finding that bone bonds directly to titanium, basis of implants."},
{"id": "heart_lung_machine", "name": "Heart-lung machine", "year": 1953, "cat": "medicine", "wiki": "Cardiopulmonary bypass", "req": ["electric_motor", "heparin", "blood_transfusion"], "desc": "A pump-oxygenator taking over circulation, enabling Gibbon's first open-heart operation."},
{"id": "echocardiography", "name": "Echocardiography", "year": 1953, "cat": "medicine", "wiki": "Echocardiography", "req": ["medical_ultrasound"], "desc": "Ultrasound imaging of the beating heart and its valves."},
{"id": "intensive_care_unit", "name": "Intensive care unit", "year": 1953, "cat": "medicine", "wiki": "Intensive care unit", "req": ["mechanical_ventilation"], "desc": "A ward for continuous monitoring and life support, first set up in Copenhagen."},
{"id": "kidney_transplant", "name": "Kidney transplantation", "year": 1954, "cat": "medicine", "wiki": "Kidney transplantation", "req": ["vascular_surgery", "hemodialysis"], "desc": "Murray's transplant between identical twins, the first successful organ transplant."},
{"id": "warfarin", "name": "Warfarin", "year": 1954, "cat": "medicine", "wiki": "Warfarin", "req": ["modern_chemistry"], "desc": "An oral anticoagulant derived from spoiled sweet clover, used for decades against clots."},
{"id": "polio_vaccine", "name": "Polio vaccine", "year": 1955, "cat": "medicine", "wiki": "Polio vaccine", "req": ["inactivated_vaccine", "cell_culture"], "desc": "Salk's inactivated (1955) and Sabin's oral (1961) vaccines that nearly eradicated polio."},
{"id": "fiberscope", "name": "Fiber-optic endoscope", "year": 1957, "cat": "medicine", "wiki": "Fiberscope", "req": ["endoscopy", "glass", "optical_fiber"], "desc": "A flexible scope using glass fiber bundles, letting doctors see inside the gut."},
{"id": "gamma_camera", "name": "Gamma camera", "year": 1957, "cat": "medicine", "wiki": "Gamma camera", "req": ["radioactive_tracer", "vacuum_tube", "scintillation_counter", "photomultiplier"], "desc": "Anger's camera imaging gamma rays from injected tracers, founding nuclear medicine imaging."},
{"id": "metformin", "name": "Metformin", "year": 1957, "cat": "medicine", "wiki": "Metformin", "req": ["herbalism", "modern_chemistry"], "desc": "A glucose-lowering drug derived from French lilac, now first-line for type 2 diabetes."},
{"id": "tricyclic_antidepressant", "name": "Tricyclic antidepressants", "year": 1957, "cat": "medicine", "wiki": "Tricyclic antidepressant", "req": ["chlorpromazine"], "desc": "Imipramine and relatives, the first widely used antidepressants."},
{"id": "pacemaker", "name": "Cardiac pacemaker", "year": 1958, "cat": "medicine", "wiki": "Pacemaker", "req": ["transistor", "ecg"], "desc": "An electronic device stimulating the heart, first fully implanted in Sweden in 1958."},
{"id": "thiazide", "name": "Thiazide diuretics", "year": 1958, "cat": "medicine", "wiki": "Thiazide", "req": ["sulfonamide"], "desc": "Oral diuretics that became the first well-tolerated treatment for high blood pressure."},
{"id": "hla", "name": "HLA tissue typing", "year": 1958, "cat": "medicine", "wiki": "Human leukocyte antigen", "req": ["abo_blood_group"], "desc": "Matching tissue antigens between donor and recipient to reduce rejection."},
{"id": "azathioprine", "name": "Azathioprine", "year": 1959, "cat": "medicine", "wiki": "Azathioprine", "req": ["modern_chemistry"], "desc": "An immunosuppressant that let kidney transplants succeed between unrelated people."},
{"id": "telehealth", "name": "Telemedicine", "year": 1959, "cat": "medicine", "wiki": "Telehealth", "req": ["television", "telephone"], "desc": "Delivering care at a distance, starting with closed-circuit TV psychiatry links."},
{"id": "oral_contraceptive", "name": "Oral contraceptive pill", "year": 1960, "cat": "medicine", "wiki": "Combined oral contraceptive pill", "req": ["norethisterone"], "desc": "A daily hormonal pill preventing ovulation, approved in the US in 1960."},
{"id": "cpr", "name": "Cardiopulmonary resuscitation", "year": 1960, "cat": "medicine", "wiki": "Cardiopulmonary resuscitation", "req": ["defibrillation", "mechanical_ventilation"], "desc": "Closed-chest compression with rescue breathing to keep circulation going in cardiac arrest."},
{"id": "benzodiazepine", "name": "Benzodiazepines", "year": 1960, "cat": "medicine", "wiki": "Benzodiazepine", "req": ["modern_chemistry"], "desc": "Anxiety and sleep drugs such as diazepam, safer in overdose than barbiturates."},
{"id": "cabg", "name": "Coronary bypass surgery", "year": 1960, "cat": "medicine", "wiki": "Coronary artery bypass surgery", "req": ["heart_lung_machine", "angiography"], "desc": "Grafting vessels around blocked coronary arteries."},
{"id": "cochlear_implant", "name": "Cochlear implant", "year": 1961, "cat": "medicine", "wiki": "Cochlear implant", "req": ["hearing_aid", "transistor"], "desc": "An implant stimulating the auditory nerve electrically, restoring hearing to the deaf."},
{"id": "ibuprofen", "name": "Ibuprofen", "year": 1961, "cat": "medicine", "wiki": "Ibuprofen", "req": ["aspirin"], "desc": "A nonsteroidal anti-inflammatory painkiller developed by Boots."},
{"id": "hip_replacement", "name": "Hip replacement", "year": 1962, "cat": "medicine", "wiki": "Hip replacement", "req": ["asepsis", "bakelite", "polyethylene"], "desc": "Charnley's low-friction joint of metal and plastic, the model for joint replacement."},
{"id": "beta_blocker", "name": "Beta blockers", "year": 1962, "cat": "medicine", "wiki": "Beta blocker", "req": ["adrenaline"], "desc": "Black's drugs blocking adrenaline receptors, treating angina, hypertension and arrhythmia."},
{"id": "quinolone", "name": "Quinolones", "year": 1962, "cat": "medicine", "wiki": "Quinolone antibiotic", "req": ["chloroquine"], "desc": "Synthetic antibiotics found as a by-product of chloroquine synthesis."},
{"id": "measles_vaccine", "name": "Measles vaccine", "year": 1963, "cat": "medicine", "wiki": "Measles vaccine", "req": ["attenuated_vaccine", "cell_culture"], "desc": "Enders' live attenuated vaccine, preventing millions of child deaths each decade."},
{"id": "spect", "name": "SPECT", "year": 1963, "cat": "medicine", "wiki": "Single-photon emission computed tomography", "req": ["gamma_camera", "electronic_computer"], "desc": "Tomographic imaging of gamma-emitting tracers, showing blood flow and function."},
{"id": "laser_surgery", "name": "Laser surgery", "year": 1963, "cat": "medicine", "wiki": "Laser surgery", "req": ["laser"], "desc": "Cutting or sealing tissue with laser light, first used on the retina."},
{"id": "dental_implant", "name": "Dental implant", "year": 1965, "cat": "medicine", "wiki": "Dental implant", "req": ["osseointegration", "dentistry", "titanium_alloy"], "desc": "A titanium post fused to the jawbone to anchor a replacement tooth."},
{"id": "liposome", "name": "Liposome", "year": 1965, "cat": "medicine", "wiki": "Liposome", "req": ["modern_chemistry"], "desc": "Lipid bilayer vesicles described by Bangham, later used to carry drugs."},
{"id": "vad", "name": "Ventricular assist device", "year": 1966, "cat": "medicine", "wiki": "Ventricular assist device", "req": ["heart_lung_machine"], "desc": "A mechanical pump supporting a failing heart, first implanted by DeBakey."},
{"id": "heart_transplant", "name": "Heart transplantation", "year": 1967, "cat": "medicine", "wiki": "Heart transplantation", "req": ["kidney_transplant", "heart_lung_machine", "azathioprine"], "desc": "Barnard's 1967 transplant of a human heart, routine once ciclosporin arrived."},
{"id": "liver_transplant", "name": "Liver transplantation", "year": 1967, "cat": "medicine", "wiki": "Liver transplantation", "req": ["kidney_transplant", "azathioprine"], "desc": "Replacing a failed liver, first with lasting success by Thomas Starzl."},
{"id": "phacoemulsification", "name": "Phacoemulsification", "year": 1967, "cat": "medicine", "wiki": "Phacoemulsification", "req": ["cataract_surgery", "medical_ultrasound"], "desc": "Kelman's method of breaking up a cataract with ultrasound through a tiny incision."},
{"id": "hsct", "name": "Bone marrow transplant", "year": 1968, "cat": "medicine", "wiki": "Hematopoietic stem cell transplantation", "req": ["hla", "blood_transfusion"], "desc": "Transplanting blood-forming stem cells to treat leukemia and immune disorders."},
{"id": "gamma_knife", "name": "Gamma Knife", "year": 1968, "cat": "medicine", "wiki": "Radiosurgery", "req": ["cobalt_therapy", "stereotactic_surgery"], "desc": "Leksell's array of cobalt beams converging on a brain target without opening the skull."},
{"id": "oral_rehydration", "name": "Oral rehydration therapy", "year": 1968, "cat": "medicine", "wiki": "Oral rehydration therapy", "req": ["iv_therapy"], "desc": "A drink of salts and sugar that treats cholera and diarrhea, saving millions of children."},
{"id": "artificial_heart", "name": "Artificial heart", "year": 1969, "cat": "medicine", "wiki": "Artificial heart", "req": ["heart_lung_machine", "artificial_heart_valve"], "desc": "A mechanical pump replacing the heart, first implanted in 1969 and as the Jarvik-7 in 1982."},
{"id": "ct_scan", "name": "CT scan", "year": 1971, "cat": "medicine", "wiki": "CT scan", "req": ["x_ray", "electronic_computer"], "desc": "Hounsfield's computed tomography, reconstructing cross-sections from many X-ray views."},
{"id": "mmr_vaccine", "name": "MMR vaccine", "year": 1971, "cat": "medicine", "wiki": "MMR vaccine", "req": ["measles_vaccine"], "desc": "A combined live vaccine against measles, mumps and rubella."},
{"id": "glucose_meter", "name": "Glucose meter", "year": 1971, "cat": "medicine", "wiki": "Glucose meter", "req": ["transistor", "biosensor"], "desc": "A portable meter reading blood sugar from a fingerstick drop."},
{"id": "artemisinin", "name": "Artemisinin", "year": 1972, "cat": "medicine", "wiki": "Artemisinin", "req": ["huangdi_neijing", "chloroquine"], "desc": "Tu Youyou's antimalarial from sweet wormwood, found by searching classical Chinese texts."},
{"id": "ehr", "name": "Electronic health record", "year": 1972, "cat": "medicine", "wiki": "Electronic health record", "req": ["electronic_computer"], "desc": "Computerized patient records, now the backbone of hospital information systems."},
{"id": "pulse_oximetry", "name": "Pulse oximetry", "year": 1974, "cat": "medicine", "wiki": "Pulse oximetry", "req": ["transistor"], "desc": "Aoyagi's clip-on sensor measuring blood oxygen by light absorption."},
{"id": "pet_scan", "name": "PET scan", "year": 1975, "cat": "medicine", "wiki": "Positron emission tomography", "req": ["radioactive_tracer", "electronic_computer"], "desc": "Imaging metabolism by detecting positron-emitting tracers such as FDG."},
{"id": "insulin_pump", "name": "Insulin pump", "year": 1976, "cat": "medicine", "wiki": "Insulin pump", "req": ["insulin", "integrated_circuit"], "desc": "A wearable pump giving continuous, programmable insulin doses."},
{"id": "mri", "name": "MRI", "year": 1977, "cat": "medicine", "wiki": "Magnetic resonance imaging", "req": ["quantum_mechanics", "electronic_computer", "nmr_spectroscopy", "superconducting_magnet"], "desc": "Imaging soft tissue with nuclear magnetic resonance, without ionizing radiation."},
{"id": "pci", "name": "Coronary angioplasty", "year": 1977, "cat": "medicine", "wiki": "Percutaneous coronary intervention", "req": ["cardiac_catheterization", "angiography"], "desc": "Gruentzig's balloon opening of a narrowed coronary artery through a catheter."},
{"id": "aciclovir", "name": "Aciclovir", "year": 1977, "cat": "medicine", "wiki": "Aciclovir", "req": ["modern_chemistry"], "desc": "The first selective antiviral drug, a nucleoside analog against herpes viruses."},
{"id": "ivf", "name": "In vitro fertilisation", "year": 1978, "cat": "medicine", "wiki": "In vitro fertilisation", "req": ["laparoscopy", "cell_culture"], "desc": "Fertilizing an egg in the lab, producing Louise Brown, the first IVF baby."},
{"id": "aed", "name": "Automated external defibrillator", "year": 1979, "cat": "medicine", "wiki": "Automated external defibrillator", "req": ["defibrillation", "microprocessor"], "desc": "A portable defibrillator that analyzes rhythm and guides untrained rescuers."},
{"id": "smallpox_eradication", "name": "Smallpox eradication", "year": 1980, "cat": "medicine", "wiki": "History of smallpox", "req": ["vaccination"], "desc": "The WHO campaign that ended smallpox, the first human disease eradicated."},
{"id": "icd", "name": "Implantable cardioverter-defibrillator", "year": 1980, "cat": "medicine", "wiki": "Implantable cardioverter-defibrillator", "req": ["defibrillation", "pacemaker"], "desc": "Mirowski's implant that detects and shocks deadly heart rhythms."},
{"id": "ace_inhibitor", "name": "ACE inhibitors", "year": 1981, "cat": "medicine", "wiki": "ACE inhibitor", "req": ["modern_chemistry"], "desc": "Captopril and successors, drugs for hypertension and heart failure modeled on snake venom peptides."},
{"id": "hepatitis_b_vaccine", "name": "Hepatitis B vaccine", "year": 1981, "cat": "medicine", "wiki": "Hepatitis B vaccine", "req": ["inactivated_vaccine"], "desc": "The first vaccine preventing a cancer (liver), later made by recombinant yeast."},
{"id": "ciclosporin", "name": "Ciclosporin", "year": 1983, "cat": "medicine", "wiki": "Ciclosporin", "req": ["azathioprine"], "desc": "A fungal immunosuppressant that made heart, liver and lung transplants routine."},
{"id": "lung_transplant", "name": "Lung transplantation", "year": 1983, "cat": "medicine", "wiki": "Lung transplantation", "req": ["ciclosporin", "heart_lung_machine"], "desc": "Replacing diseased lungs, first with lasting success in Toronto."},
{"id": "digital_radiography", "name": "Digital radiography", "year": 1983, "cat": "medicine", "wiki": "Digital radiography", "req": ["x_ray", "integrated_circuit"], "desc": "Capturing X-ray images electronically instead of on film."},
{"id": "hiv_test", "name": "HIV test", "year": 1985, "cat": "medicine", "wiki": "Diagnosis of HIV/AIDS", "req": ["elisa"], "desc": "Antibody screening for HIV, protecting the blood supply from 1985."},
{"id": "robotic_surgery", "name": "Robot-assisted surgery", "year": 1985, "cat": "medicine", "wiki": "Robotic surgery", "req": ["laparoscopy", "microprocessor"], "desc": "Surgery with robotic instruments, from the PUMA biopsy robot onward."},
{"id": "monoclonal_antibody_therapy", "name": "Monoclonal antibody therapy", "year": 1986, "cat": "medicine", "wiki": "Monoclonal antibody therapy", "req": ["hybridoma"], "desc": "Drugs made of antibodies targeting one molecule, first muromonab for transplant rejection."},
{"id": "coronary_stent", "name": "Coronary stent", "year": 1986, "cat": "medicine", "wiki": "Coronary stent", "req": ["pci", "stainless_steel"], "desc": "A mesh tube keeping a reopened artery open after angioplasty."},
{"id": "zidovudine", "name": "Zidovudine", "year": 1987, "cat": "medicine", "wiki": "Zidovudine", "req": ["modern_chemistry"], "desc": "AZT, the first approved drug against HIV."},
{"id": "ssri", "name": "SSRIs", "year": 1987, "cat": "medicine", "wiki": "Selective serotonin reuptake inhibitor", "req": ["tricyclic_antidepressant"], "desc": "Antidepressants such as fluoxetine with fewer side effects than tricyclics."},
{"id": "statin", "name": "Statins", "year": 1987, "cat": "medicine", "wiki": "Statin", "req": ["modern_chemistry"], "desc": "Cholesterol-lowering drugs blocking HMG-CoA reductase, cutting heart attacks and strokes."},
{"id": "prk", "name": "Photorefractive keratectomy", "year": 1987, "cat": "medicine", "wiki": "Photorefractive keratectomy", "req": ["laser"], "desc": "Reshaping the cornea with an excimer laser to correct vision."},
{"id": "deep_brain_stimulation", "name": "Deep brain stimulation", "year": 1987, "cat": "medicine", "wiki": "Deep brain stimulation", "req": ["stereotactic_surgery", "pacemaker"], "desc": "Implanted electrodes delivering pulses to brain targets to treat Parkinson's tremor."},
{"id": "lateral_flow_test", "name": "Lateral flow test", "year": 1988, "cat": "medicine", "wiki": "Lateral flow test", "req": ["elisa", "monoclonal_antibody_therapy"], "desc": "A paper strip giving a quick visual antigen or antibody result, as in home pregnancy tests."},
{"id": "gene_therapy", "name": "Gene therapy", "year": 1990, "cat": "medicine", "wiki": "Gene therapy", "req": ["recombinant_dna", "viral_vector"], "desc": "Treating disease by delivering genes into cells, first tried for ADA immunodeficiency."},
{"id": "lasik", "name": "LASIK", "year": 1990, "cat": "medicine", "wiki": "LASIK", "req": ["prk"], "desc": "Laser reshaping of the cornea under a surgical flap, the common vision correction surgery."},
{"id": "pgd", "name": "Preimplantation genetic diagnosis", "year": 1990, "cat": "medicine", "wiki": "Preimplantation genetic diagnosis", "req": ["ivf", "pcr"], "desc": "Testing IVF embryos for genetic disease before transfer."},
{"id": "ebm", "name": "Evidence-based medicine", "year": 1991, "cat": "medicine", "wiki": "Evidence-based medicine", "req": ["rct"], "desc": "Basing clinical decisions on systematic review of trial evidence."},
{"id": "fmri", "name": "Functional MRI", "year": 1991, "cat": "medicine", "wiki": "Functional magnetic resonance imaging", "req": ["mri"], "desc": "MRI that maps brain activity through changes in blood oxygen."},
{"id": "imrt", "name": "IMRT", "year": 1994, "cat": "medicine", "wiki": "External beam radiotherapy", "req": ["linear_accelerator", "ct_scan"], "desc": "Computer-shaped radiation beams that conform dose closely to a tumor."},
{"id": "protease_inhibitor", "name": "HIV protease inhibitors", "year": 1995, "cat": "medicine", "wiki": "Protease inhibitor (pharmacology)", "req": ["zidovudine"], "desc": "Drugs such as saquinavir blocking HIV's protease, key to combination therapy."},
{"id": "haart", "name": "Combination antiretroviral therapy", "year": 1996, "cat": "medicine", "wiki": "Management of HIV/AIDS", "req": ["zidovudine", "protease_inhibitor"], "desc": "Three-drug regimens that turned HIV from fatal to a chronic, manageable condition."},
{"id": "clear_aligners", "name": "Clear aligners", "year": 1997, "cat": "medicine", "wiki": "Clear aligners", "req": ["dental_braces", "personal_computer", "3d_printing", "computer_aided_design"], "desc": "Computer-designed transparent plastic trays that straighten teeth in steps."},
{"id": "trastuzumab", "name": "Trastuzumab", "year": 1998, "cat": "medicine", "wiki": "Trastuzumab", "req": ["monoclonal_antibody_therapy", "recombinant_dna"], "desc": "A humanized antibody against HER2 breast cancer, a model of targeted therapy."},
{"id": "antisense_therapy", "name": "Antisense therapy", "year": 1998, "cat": "medicine", "wiki": "Antisense therapy", "req": ["dna_double_helix"], "desc": "Short synthetic nucleic acids that block a target RNA, first approved as fomivirsen."},
{"id": "hand_transplant", "name": "Hand transplantation", "year": 1998, "cat": "medicine", "wiki": "Hand transplantation", "req": ["ciclosporin", "microsurgery"], "desc": "Transplanting a donor hand, the first composite tissue transplant."},
{"id": "bci", "name": "Brain-computer interface", "year": 1998, "cat": "medicine", "wiki": "Brain–computer interface", "req": ["eeg", "electronic_computer"], "desc": "Implants or sensors letting paralyzed people control computers by thought."},
{"id": "cgm", "name": "Continuous glucose monitor", "year": 1999, "cat": "medicine", "wiki": "Continuous glucose monitor", "req": ["glucose_meter", "integrated_circuit"], "desc": "A skin sensor tracking blood sugar every few minutes."},
{"id": "da_vinci", "name": "Da Vinci Surgical System", "year": 2000, "cat": "medicine", "wiki": "Da Vinci Surgical System", "req": ["robotic_surgery"], "desc": "The surgeon-controlled robot that made robotic laparoscopy widespread."},
{"id": "imatinib", "name": "Imatinib", "year": 2001, "cat": "medicine", "wiki": "Imatinib", "req": ["chemotherapy"], "desc": "A kinase inhibitor against chronic myeloid leukemia, the landmark of targeted cancer drugs."},
{"id": "capsule_endoscopy", "name": "Capsule endoscopy", "year": 2001, "cat": "medicine", "wiki": "Capsule endoscopy", "req": ["endoscopy", "integrated_circuit"], "desc": "A swallowed camera pill imaging the small intestine."},
{"id": "remote_surgery", "name": "Remote surgery", "year": 2001, "cat": "medicine", "wiki": "Remote surgery", "req": ["da_vinci", "internet"], "desc": "Operating on a patient from far away, as in the transatlantic Lindbergh operation."},
{"id": "tavr", "name": "Transcatheter valve replacement", "year": 2002, "cat": "medicine", "wiki": "Transcatheter aortic valve replacement", "req": ["pci", "artificial_heart_valve"], "desc": "Implanting a new aortic valve through a catheter instead of open-heart surgery."},
{"id": "glp1_agonist", "name": "GLP-1 receptor agonists", "year": 2005, "cat": "medicine", "wiki": "GLP-1 receptor agonist", "req": ["insulin", "recombinant_dna"], "desc": "Gut-hormone mimics such as exenatide and semaglutide that treat diabetes and obesity."},
{"id": "hpv_vaccine", "name": "HPV vaccine", "year": 2006, "cat": "medicine", "wiki": "HPV vaccine", "req": ["hepatitis_b_vaccine", "recombinant_dna"], "desc": "A virus-like particle vaccine preventing cervical and other cancers."},
{"id": "checkpoint_inhibitor", "name": "Checkpoint inhibitors", "year": 2011, "cat": "medicine", "wiki": "Checkpoint inhibitor", "req": ["monoclonal_antibody_therapy"], "desc": "Antibodies releasing immune brakes such as CTLA-4 and PD-1 so T cells attack cancer."},
{"id": "prep", "name": "HIV PrEP", "year": 2012, "cat": "medicine", "wiki": "Pre-exposure prophylaxis", "req": ["haart"], "desc": "Taking antiretrovirals in advance to prevent HIV infection."},
{"id": "retinal_implant", "name": "Retinal implant", "year": 2013, "cat": "medicine", "wiki": "Retinal implant", "req": ["cochlear_implant", "integrated_circuit"], "desc": "An electrode array stimulating the retina to give partial sight to the blind."},
{"id": "sofosbuvir", "name": "Sofosbuvir", "year": 2013, "cat": "medicine", "wiki": "Sofosbuvir", "req": ["aciclovir"], "desc": "A nucleotide antiviral that made hepatitis C curable in weeks."},
{"id": "artificial_pancreas", "name": "Artificial pancreas", "year": 2016, "cat": "medicine", "wiki": "Automated insulin delivery system", "req": ["insulin_pump", "cgm"], "desc": "A closed loop of glucose sensor, algorithm and pump that doses insulin automatically."},
{"id": "car_t", "name": "CAR T-cell therapy", "year": 2017, "cat": "medicine", "wiki": "CAR T cell", "req": ["gene_therapy", "monoclonal_antibody_therapy", "viral_vector"], "desc": "Patients' T cells engineered with an antibody-based receptor to kill cancer."},
{"id": "voretigene", "name": "Voretigene neparvovec", "year": 2017, "cat": "medicine", "wiki": "Voretigene neparvovec", "req": ["gene_therapy", "viral_vector"], "desc": "An AAV gene therapy for inherited blindness, the first in vivo gene therapy approved in the US."},
{"id": "patisiran", "name": "Patisiran", "year": 2018, "cat": "medicine", "wiki": "Patisiran", "req": ["antisense_therapy", "liposome", "sirna"], "desc": "The first RNA interference drug, delivered in lipid nanoparticles."},
{"id": "ai_healthcare", "name": "Medical AI", "year": 2018, "cat": "medicine", "wiki": "Artificial intelligence in healthcare", "req": ["artificial_intelligence", "digital_radiography", "deep_learning"], "desc": "Algorithms reading scans and images, first cleared for autonomous diabetic retinopathy diagnosis."},
{"id": "viral_vector_vaccine", "name": "Viral vector vaccine", "year": 2019, "cat": "medicine", "wiki": "Viral vector vaccine", "req": ["recombinant_dna", "viral_vector"], "desc": "Vaccines using a harmless virus to deliver an antigen gene, first licensed against Ebola."},
{"id": "mrna_vaccine", "name": "mRNA vaccine", "year": 2020, "cat": "medicine", "wiki": "MRNA vaccine", "req": ["liposome", "recombinant_dna", "patisiran"], "desc": "Vaccines delivering lipid-wrapped messenger RNA, first deployed at scale against COVID-19."},
{"id": "malaria_vaccine", "name": "Malaria vaccine", "year": 2021, "cat": "medicine", "wiki": "Malaria vaccine", "req": ["hepatitis_b_vaccine"], "desc": "RTS,S and R21, the first vaccines against a parasitic disease."},
{"id": "xenotransplantation", "name": "Xenotransplantation", "year": 2022, "cat": "medicine", "wiki": "Xenotransplantation", "req": ["heart_transplant", "recombinant_dna", "crispr_cas9"], "desc": "Transplanting gene-edited pig organs into humans, first a heart in 2022."},
{"id": "exa_cel", "name": "CRISPR gene therapy", "year": 2023, "cat": "medicine", "wiki": "Exagamglogene autotemcel", "req": ["gene_therapy", "hsct", "crispr_cas9"], "desc": "Casgevy, the first approved CRISPR-edited therapy, for sickle cell disease."},
{"id": "spear_thrower", "name": "Spear-thrower", "year": -30000, "cat": "military", "wiki": "Spear-thrower", "req": ["spear"], "desc": "The atlatl lengthened the thrower's arm, greatly increasing the range and force of thrown darts."},
{"id": "sling", "name": "Sling", "year": -7000, "cat": "military", "wiki": "Sling (weapon)", "req": ["cordage"], "desc": "A cord-and-pouch projectile weapon used from the Neolithic to Roman times."},
{"id": "mace", "name": "Mace", "year": -12000, "cat": "military", "wiki": "Mace (bludgeon)", "req": ["stone_tools"], "desc": "A club with a heavy stone or metal head, among the earliest weapons made specifically for combat."},
{"id": "longbow", "name": "Longbow", "year": -3300, "cat": "military", "wiki": "Longbow", "req": ["bow_and_arrow"], "desc": "A tall self bow, known from Ötzi's equipment and later decisive for English armies at Crécy and Agincourt."},
{"id": "composite_bow", "name": "Composite bow", "year": -2000, "cat": "military", "wiki": "Composite bow", "req": ["bow_and_arrow", "domestication_of_animals"], "desc": "Bows laminated from wood, horn and sinew gave great power in a short length, ideal for mounted archers."},
{"id": "dagger", "name": "Dagger", "year": -3500, "cat": "military", "wiki": "Dagger", "req": ["smelting", "stone_tools"], "desc": "Short stabbing blades, first in flint and then copper and bronze, the ancestor of the sword."},
{"id": "shield", "name": "Shield", "year": -3000, "cat": "military", "wiki": "Shield", "req": ["stone_tools", "domestication_of_animals"], "desc": "Hand-held barriers of wood, hide and later metal, used by nearly every ancient army."},
{"id": "helmet", "name": "Helmet", "year": -2500, "cat": "military", "wiki": "Helmet", "req": ["bronze"], "desc": "Metal head protection appears in Sumer around 2500 BC, as in the helmet of Meskalamdug at Ur."},
{"id": "scale_armour", "name": "Scale armour", "year": -1500, "cat": "military", "wiki": "Scale armour", "req": ["bronze", "weaving"], "desc": "Overlapping metal scales sewn to a backing, worn by charioteers in the Bronze Age Near East."},
{"id": "lamellar_armour", "name": "Lamellar armour", "year": -800, "cat": "military", "wiki": "Lamellar armour", "req": ["scale_armour", "cordage"], "desc": "Small plates laced together in rows, widely used from Assyria to East Asia and the steppe."},
{"id": "mail_armour", "name": "Mail", "year": -400, "cat": "military", "wiki": "Chain mail", "req": ["iron_working"], "desc": "Interlinked iron rings, probably invented by the Celts, gave flexible protection for nearly two thousand years."},
{"id": "plate_armour", "name": "Plate armour", "year": 1400, "cat": "military", "wiki": "Plate armour", "req": ["steel", "mail_armour"], "desc": "Full suits of shaped steel plates protected late medieval knights against swords and arrows."},
{"id": "chariot", "name": "War chariot", "year": -2000, "cat": "military", "wiki": "Chariot", "req": ["wheel", "domestication_of_animals", "spoked_wheel", "horse_bit"], "desc": "Spoked-wheel horse chariots of the Sintashta culture became the elite striking arm of Bronze Age armies."},
{"id": "bronze_sword", "name": "Bronze Age sword", "year": -1700, "cat": "military", "wiki": "Bronze Age sword", "req": ["bronze", "dagger"], "desc": "Lengthened bronze blades produced the first true swords in the Aegean and Near East."},
{"id": "iron_sword", "name": "Iron Age sword", "year": -1200, "cat": "military", "wiki": "Iron Age sword", "req": ["iron_working", "bronze_sword"], "desc": "Swords of wrought iron and later steel replaced bronze as iron working spread."},
{"id": "pike", "name": "Pike", "year": -350, "cat": "military", "wiki": "Pike (weapon)", "req": ["spear"], "desc": "Very long infantry spears such as the Macedonian sarissa, revived by Swiss pikemen in the 15th century."},
{"id": "pilum", "name": "Pilum", "year": -300, "cat": "military", "wiki": "Pilum", "req": ["spear", "iron_working"], "desc": "The Roman heavy javelin, whose soft iron shank bent on impact to disable enemy shields."},
{"id": "defensive_wall", "name": "Defensive wall", "year": -8000, "cat": "military", "wiki": "Defensive wall", "req": ["mudbrick"], "desc": "Walls around settlements, beginning with Neolithic Jericho, protected communities from attack."},
{"id": "castle", "name": "Castle", "year": 900, "cat": "military", "wiki": "Castle", "req": ["defensive_wall", "lime_mortar"], "desc": "Fortified residences of medieval lords, evolving from timber mottes to stone keeps and concentric walls."},
{"id": "bastion_fort", "name": "Bastion fort", "year": 1500, "cat": "military", "wiki": "Bastion fort", "req": ["castle", "cannon"], "desc": "Low angled earth and masonry ramparts, the trace italienne, resisted cannon fire and covered approaches with flanking fire."},
{"id": "battering_ram", "name": "Battering ram", "year": -2400, "cat": "military", "wiki": "Battering ram", "req": ["cordage", "lever"], "desc": "Heavy beams for breaking gates and walls, depicted in Egyptian and Assyrian sieges."},
{"id": "siege_tower", "name": "Siege tower", "year": -880, "cat": "military", "wiki": "Siege tower", "req": ["wheel", "battering_ram"], "desc": "Wheeled towers let attackers reach the tops of walls, used by the Assyrians and later the Greeks and Romans."},
{"id": "crossbow", "name": "Crossbow", "year": -650, "cat": "military", "wiki": "Crossbow", "req": ["bow_and_arrow", "bronze"], "desc": "A bow mounted on a stock with a mechanical trigger, used on a large scale in Warring States China."},
{"id": "gastraphetes", "name": "Gastraphetes", "year": -420, "cat": "military", "wiki": "Gastraphetes", "req": ["composite_bow"], "desc": "A Greek belly-bow drawn using body weight, the forerunner of the catapult."},
{"id": "catapult", "name": "Catapult", "year": -399, "cat": "military", "wiki": "Catapult", "req": ["gastraphetes", "lever"], "desc": "Engineers of Dionysius I of Syracuse built mechanical artillery to hurl bolts and stones at sieges."},
{"id": "ballista", "name": "Ballista", "year": -340, "cat": "military", "wiki": "Ballista", "req": ["catapult", "cordage"], "desc": "Torsion-powered bolt and stone throwers using twisted sinew springs, standard in Hellenistic and Roman armies."},
{"id": "traction_trebuchet", "name": "Traction trebuchet", "year": -400, "cat": "military", "wiki": "Mangonel", "req": ["lever", "cordage"], "desc": "A Chinese lever-arm siege engine powered by crews pulling ropes, which spread west by the 6th century."},
{"id": "trebuchet", "name": "Counterweight trebuchet", "year": 1165, "cat": "military", "wiki": "Trebuchet", "req": ["traction_trebuchet"], "desc": "A falling counterweight powered this siege engine, able to hurl stones of over 100 kg against walls."},
{"id": "trireme", "name": "Trireme", "year": -700, "cat": "military", "wiki": "Trireme", "req": ["sail", "naval_ram", "bireme", "bronze"], "desc": "A Greek warship with three banks of oars, built to ram enemy vessels."},
{"id": "naval_ram", "name": "Naval ram", "year": -800, "cat": "military", "wiki": "Naval ram", "req": ["bronze", "sail"], "desc": "A bronze-sheathed beak on a warship's bow used to hole enemy hulls."},
{"id": "greek_fire", "name": "Greek fire", "year": 672, "cat": "military", "wiki": "Greek fire", "req": ["distillation"], "desc": "An incendiary liquid projected from siphons by the Byzantine navy, credited with defending Constantinople."},
{"id": "fire_arrow", "name": "Fire arrow", "year": 904, "cat": "military", "wiki": "Fire arrow", "req": ["gunpowder", "bow_and_arrow"], "desc": "Arrows carrying gunpowder incendiaries, first recorded in Song-era China."},
{"id": "fire_lance", "name": "Fire lance", "year": 950, "cat": "military", "wiki": "Fire lance", "req": ["gunpowder", "spear"], "desc": "A tube of gunpowder on a spear that fired flame and shrapnel, the ancestor of all guns."},
{"id": "grenade", "name": "Grenade", "year": 1000, "cat": "military", "wiki": "Grenade", "req": ["gunpowder", "pottery"], "desc": "Ceramic and iron shells filled with gunpowder thrown by hand, first used in Song China."},
{"id": "land_mine", "name": "Land mine", "year": 1277, "cat": "military", "wiki": "Land mine", "req": ["gunpowder"], "desc": "Buried explosive devices were first used by Song forces against the Mongols."},
{"id": "hand_cannon", "name": "Hand cannon", "year": 1288, "cat": "military", "wiki": "Hand cannon", "req": ["fire_lance", "bronze", "gunpowder"], "desc": "A metal-barrelled firearm, as in the Heilongjiang hand cannon of about 1288."},
{"id": "cannon", "name": "Cannon", "year": 1326, "cat": "military", "wiki": "Cannon", "req": ["hand_cannon", "cast_iron", "gunpowder"], "desc": "Large gunpowder tubes firing projectiles appeared in Europe by 1326, reshaping sieges."},
{"id": "hwacha", "name": "Hwacha", "year": 1409, "cat": "military", "wiki": "Hwacha", "req": ["fire_arrow"], "desc": "A Korean cart that launched dozens of rocket-propelled arrows at once."},
{"id": "matchlock", "name": "Matchlock", "year": 1411, "cat": "military", "wiki": "Matchlock", "req": ["hand_cannon", "lever"], "desc": "A lever lowering a burning match to the priming pan, the first trigger mechanism for firearms."},
{"id": "arquebus", "name": "Arquebus", "year": 1450, "cat": "military", "wiki": "Arquebus", "req": ["matchlock"], "desc": "A shoulder-fired matchlock gun that became the standard infantry firearm of the 16th century."},
{"id": "mortar_weapon", "name": "Mortar", "year": 1451, "cat": "military", "wiki": "Mortar (weapon)", "req": ["cannon"], "desc": "Short-barrelled guns firing at high angles, first used at the siege of Constantinople."},
{"id": "rifling", "name": "Rifling", "year": 1498, "cat": "military", "wiki": "Rifling", "req": ["arquebus"], "desc": "Spiral grooves in a barrel spin the bullet, greatly improving accuracy."},
{"id": "wheellock", "name": "Wheellock", "year": 1505, "cat": "military", "wiki": "Wheellock", "req": ["matchlock", "steel"], "desc": "A spring-driven steel wheel struck sparks from pyrite, allowing guns to be carried ready to fire."},
{"id": "musket", "name": "Musket", "year": 1521, "cat": "military", "wiki": "Musket", "req": ["arquebus"], "desc": "A heavier long gun able to pierce plate armour, used by massed infantry for three centuries."},
{"id": "naval_mine", "name": "Naval mine", "year": 1549, "cat": "military", "wiki": "Naval mine", "req": ["land_mine"], "desc": "Floating explosive devices against ships were described in Ming China; Bushnell used them in 1777."},
{"id": "flintlock", "name": "Flintlock", "year": 1610, "cat": "military", "wiki": "Flintlock", "req": ["wheellock"], "desc": "Marin le Bourgeoys' flint-striking lock was cheaper and more reliable, standard until the 1840s."},
{"id": "bayonet", "name": "Bayonet", "year": 1647, "cat": "military", "wiki": "Bayonet", "req": ["musket", "iron_sword"], "desc": "Blades fixed to musket muzzles let musketeers defend themselves and made the pike obsolete."},
{"id": "ship_of_the_line", "name": "Ship of the line", "year": 1650, "cat": "military", "wiki": "Ship of the line", "req": ["cannon", "sail"], "desc": "Large sailing warships carrying rows of broadside guns, built to fight in line of battle."},
{"id": "howitzer", "name": "Howitzer", "year": 1693, "cat": "military", "wiki": "Howitzer", "req": ["mortar_weapon", "cannon"], "desc": "Artillery firing explosive shells on curved trajectories, between a gun and a mortar."},
{"id": "mysorean_rockets", "name": "Mysorean rockets", "year": 1780, "cat": "military", "wiki": "Mysorean rockets", "req": ["rocket", "iron_working"], "desc": "Iron-cased rockets used by Hyder Ali and Tipu Sultan against the British East India Company."},
{"id": "congreve_rocket", "name": "Congreve rocket", "year": 1804, "cat": "military", "wiki": "Congreve rocket", "req": ["mysorean_rockets"], "desc": "William Congreve's British military rockets were based on captured Mysorean designs."},
{"id": "percussion_cap", "name": "Percussion cap", "year": 1820, "cat": "military", "wiki": "Percussion cap", "req": ["flintlock", "modern_chemistry"], "desc": "A copper cap of shock-sensitive fulminate made ignition reliable in wet weather."},
{"id": "dreyse_needle_gun", "name": "Dreyse needle gun", "year": 1836, "cat": "military", "wiki": "Dreyse needle gun", "req": ["percussion_cap", "rifling"], "desc": "The first military bolt-action breech-loading rifle, adopted by Prussia, which allowed firing while prone."},
{"id": "revolver", "name": "Revolver", "year": 1836, "cat": "military", "wiki": "Revolver", "req": ["percussion_cap", "interchangeable_parts"], "desc": "Samuel Colt's revolving-cylinder pistol, mass-produced from interchangeable parts."},
{"id": "telescopic_sight", "name": "Telescopic sight", "year": 1835, "cat": "military", "wiki": "Telescopic sight", "req": ["refracting_telescope", "rifling"], "desc": "Telescopes mounted on rifles for precise aiming, used by sharpshooters from the 1830s."},
{"id": "cartridge", "name": "Metallic cartridge", "year": 1846, "cat": "military", "wiki": "Cartridge (firearms)", "req": ["percussion_cap"], "desc": "Self-contained metal cases holding primer, powder and bullet made breech-loading practical."},
{"id": "minie_ball", "name": "Minié ball", "year": 1849, "cat": "military", "wiki": "Minié ball", "req": ["rifling", "percussion_cap"], "desc": "A hollow-based bullet that expanded into rifling, making rifles as fast to load as muskets."},
{"id": "armstrong_gun", "name": "Armstrong gun", "year": 1855, "cat": "military", "wiki": "Armstrong gun", "req": ["rifling", "cannon", "steel"], "desc": "William Armstrong's rifled breech-loading cannon introduced built-up steel construction."},
{"id": "ironclad", "name": "Ironclad warship", "year": 1859, "cat": "military", "wiki": "Ironclad warship", "req": ["steamship", "cannon", "iron_working"], "desc": "Steam warships protected by iron armour, beginning with the French Gloire, made wooden fleets obsolete."},
{"id": "repeating_rifle", "name": "Repeating rifle", "year": 1860, "cat": "military", "wiki": "Repeating firearm", "req": ["cartridge"], "desc": "Magazine-fed rifles such as the Spencer and Henry let soldiers fire several shots without reloading."},
{"id": "gatling_gun", "name": "Gatling gun", "year": 1862, "cat": "military", "wiki": "Gatling gun", "req": ["cartridge", "interchangeable_parts"], "desc": "Richard Gatling's hand-cranked multi-barrel gun delivered sustained rapid fire."},
{"id": "torpedo", "name": "Torpedo", "year": 1866, "cat": "military", "wiki": "Torpedo", "req": ["naval_mine"], "desc": "Robert Whitehead's self-propelled underwater weapon was powered by compressed air."},
{"id": "bolt_action", "name": "Bolt-action rifle", "year": 1871, "cat": "military", "wiki": "Bolt action", "req": ["dreyse_needle_gun", "cartridge"], "desc": "The Mauser Model 1871 established the bolt action used by most rifles through two world wars."},
{"id": "maxim_gun", "name": "Maxim gun", "year": 1884, "cat": "military", "wiki": "Maxim gun", "req": ["gatling_gun", "cartridge"], "desc": "Hiram Maxim's recoil-operated gun was the first fully automatic machine gun."},
{"id": "semi_automatic_rifle", "name": "Semi-automatic rifle", "year": 1885, "cat": "military", "wiki": "Semi-automatic rifle", "req": ["bolt_action"], "desc": "Rifles that reload themselves for each trigger pull, beginning with Mannlicher's designs."},
{"id": "semi_automatic_pistol", "name": "Semi-automatic pistol", "year": 1893, "cat": "military", "wiki": "Semi-automatic pistol", "req": ["revolver", "smokeless_powder"], "desc": "Self-loading pistols fed from a magazine, beginning with the Borchardt C-93."},
{"id": "shaped_charge", "name": "Shaped charge", "year": 1888, "cat": "military", "wiki": "Shaped charge", "req": ["nitrocellulose"], "desc": "Charles Munroe observed that a hollow in an explosive focuses its force, later used against armour."},
{"id": "destroyer", "name": "Destroyer", "year": 1892, "cat": "military", "wiki": "Destroyer", "req": ["torpedo", "steamship"], "desc": "Fast warships built to counter torpedo boats, later escorts and fleet workhorses."},
{"id": "canon_de_75", "name": "Canon de 75 modèle 1897", "year": 1897, "cat": "military", "wiki": "Canon de 75 modèle 1897", "req": ["armstrong_gun", "smokeless_powder"], "desc": "The French 75 was the first field gun with a hydropneumatic recoil mechanism, enabling rapid fire."},
{"id": "submarine", "name": "Military submarine", "year": 1900, "cat": "military", "wiki": "Submarine", "req": ["torpedo", "internal_combustion_engine", "electric_motor", "oar", "scientific_method"], "desc": "John Holland's petrol-electric submarine, bought by the US Navy in 1900, set the pattern for modern submarines."},
{"id": "flamethrower", "name": "Flamethrower", "year": 1901, "cat": "military", "wiki": "Flamethrower", "req": ["oil_refining"], "desc": "Richard Fiedler's portable flamethrower was first used by German troops in 1915."},
{"id": "armoured_car", "name": "Armoured car", "year": 1902, "cat": "military", "wiki": "Armored car (military)", "req": ["automobile", "maxim_gun"], "desc": "Armoured motor vehicles carrying machine guns, the predecessors of the tank."},
{"id": "light_machine_gun", "name": "Light machine gun", "year": 1902, "cat": "military", "wiki": "Light machine gun", "req": ["maxim_gun", "smokeless_powder"], "desc": "Portable automatic weapons such as the Madsen let infantry squads carry machine-gun fire."},
{"id": "electronic_warfare", "name": "Electronic warfare", "year": 1904, "cat": "military", "wiki": "Electronic warfare", "req": ["radio"], "desc": "Radio jamming during the Russo-Japanese War began the contest over the electromagnetic spectrum."},
{"id": "dreadnought", "name": "Dreadnought", "year": 1906, "cat": "military", "wiki": "Dreadnought", "req": ["ironclad", "gun_turret", "armstrong_gun", "steam_turbine"], "desc": "HMS Dreadnought's all-big-gun armament and steam turbines rendered earlier battleships obsolete."},
{"id": "bomber", "name": "Bomber", "year": 1913, "cat": "military", "wiki": "Bomber", "req": ["airplane"], "desc": "Aircraft designed to drop bombs, beginning with Sikorsky's Ilya Muromets."},
{"id": "synchronization_gear", "name": "Synchronization gear", "year": 1915, "cat": "military", "wiki": "Synchronization gear", "req": ["light_machine_gun", "airplane"], "desc": "Mechanisms timing a machine gun to fire through a spinning propeller, which created the fighter."},
{"id": "fighter_aircraft", "name": "Fighter aircraft", "year": 1915, "cat": "military", "wiki": "Fighter aircraft", "req": ["synchronization_gear"], "desc": "The Fokker Eindecker and later fighters were built to destroy other aircraft."},
{"id": "chemical_warfare", "name": "Chemical warfare", "year": 1915, "cat": "military", "wiki": "Chemical warfare", "req": ["modern_chemistry", "electrolysis"], "desc": "Large-scale chlorine gas attacks at Ypres in 1915 began modern chemical warfare, later banned by treaty."},
{"id": "gas_mask", "name": "Gas mask", "year": 1915, "cat": "military", "wiki": "Gas mask", "req": ["chemical_warfare"], "desc": "Respirators with chemical filters were rushed into service to protect troops against poison gas."},
{"id": "combat_helmet", "name": "Combat helmet", "year": 1915, "cat": "military", "wiki": "Combat helmet", "req": ["helmet", "steel"], "desc": "Steel helmets such as the Adrian and Brodie cut head wounds from shell fragments in the First World War."},
{"id": "depth_charge", "name": "Depth charge", "year": 1916, "cat": "military", "wiki": "Depth charge", "req": ["naval_mine"], "desc": "Explosive canisters fused to detonate at depth, the first effective anti-submarine weapon."},
{"id": "tank", "name": "Tank", "year": 1916, "cat": "military", "wiki": "Tank", "req": ["armoured_car", "internal_combustion_engine", "tractor"], "desc": "British tracked armoured vehicles first went into action at the Somme in 1916."},
{"id": "submachine_gun", "name": "Submachine gun", "year": 1918, "cat": "military", "wiki": "Submachine gun", "req": ["semi_automatic_pistol", "light_machine_gun"], "desc": "Automatic weapons firing pistol cartridges, such as the MP 18, for close combat."},
{"id": "aircraft_carrier", "name": "Aircraft carrier", "year": 1918, "cat": "military", "wiki": "Aircraft carrier", "req": ["airplane", "dreadnought"], "desc": "HMS Argus was the first ship with a full-length flight deck, later the core of naval power."},
{"id": "norden_bombsight", "name": "Norden bombsight", "year": 1932, "cat": "military", "wiki": "Norden bombsight", "req": ["bomber", "gyroscope"], "desc": "A gyroscopically stabilized analogue computer for high-altitude bomb aiming."},
{"id": "nerve_agent", "name": "Nerve agent", "year": 1936, "cat": "military", "wiki": "Nerve agent", "req": ["chemical_warfare"], "desc": "Gerhard Schrader's discovery of tabun led to the most lethal class of chemical weapons."},
{"id": "night_vision", "name": "Night-vision device", "year": 1939, "cat": "military", "wiki": "Night-vision device", "req": ["photomultiplier"], "desc": "Infrared image converters first used in the Second World War, later passive image intensifiers."},
{"id": "multiple_rocket_launcher", "name": "Multiple rocket launcher", "year": 1939, "cat": "military", "wiki": "Multiple rocket launcher", "req": ["rocket", "hwacha"], "desc": "Truck-mounted salvo launchers such as the Soviet Katyusha saturated areas with rockets."},
{"id": "proximity_fuze", "name": "Proximity fuze", "year": 1940, "cat": "military", "wiki": "Proximity fuze", "req": ["radar", "vacuum_tube"], "desc": "A tiny radar in a shell detonated it near its target, greatly increasing anti-aircraft effectiveness."},
{"id": "bazooka", "name": "Bazooka", "year": 1942, "cat": "military", "wiki": "Bazooka", "req": ["shaped_charge", "rocket"], "desc": "A shoulder-fired rocket launcher with a shaped-charge warhead that gave infantry anti-tank firepower."},
{"id": "flak_jacket", "name": "Flak jacket", "year": 1943, "cat": "military", "wiki": "Flak jacket", "req": ["plate_armour", "combat_helmet"], "desc": "Body armour of steel or nylon plates protected bomber crews against shell fragments."},
{"id": "chaff", "name": "Chaff", "year": 1943, "cat": "military", "wiki": "Chaff (countermeasure)", "req": ["radar", "electronic_warfare"], "desc": "Clouds of foil strips swamped enemy radar, first used in the 1943 raid on Hamburg."},
{"id": "precision_guided_munition", "name": "Precision-guided munition", "year": 1943, "cat": "military", "wiki": "Precision-guided munition", "req": ["bomber", "radio"], "desc": "The radio-guided German Fritz X sank the battleship Roma, the first guided bomb success."},
{"id": "homing_torpedo", "name": "Acoustic homing torpedo", "year": 1943, "cat": "military", "wiki": "Acoustic torpedo", "req": ["torpedo", "sonar"], "desc": "Torpedoes that steered toward a target's propeller noise, first used by Germany and the US."},
{"id": "cruise_missile", "name": "Cruise missile", "year": 1944, "cat": "military", "wiki": "Cruise missile", "req": ["jet_engine", "gyroscope"], "desc": "The pulse-jet V-1 flying bomb was the first operational cruise missile."},
{"id": "ballistic_missile", "name": "Ballistic missile", "year": 1944, "cat": "military", "wiki": "Ballistic missile", "req": ["liquid_rocket", "inertial_navigation", "turbopump"], "desc": "The German V-2 was the first long-range guided ballistic missile."},
{"id": "assault_rifle", "name": "Assault rifle", "year": 1944, "cat": "military", "wiki": "Assault rifle", "req": ["submachine_gun", "semi_automatic_rifle"], "desc": "The StG 44 fired an intermediate cartridge with selective fire, the pattern of modern infantry rifles."},
{"id": "jet_fighter", "name": "Messerschmitt Me 262", "year": 1944, "cat": "military", "wiki": "Messerschmitt Me 262", "req": ["fighter_aircraft", "jet_engine"], "desc": "The first operational jet fighter, considerably faster than piston-engined opponents."},
{"id": "hydrogen_bomb", "name": "Thermonuclear weapon", "year": 1952, "cat": "military", "wiki": "Thermonuclear weapon", "req": ["nuclear_weapon"], "desc": "The US Ivy Mike test used a fission primary to ignite fusion, yielding about 10 megatons."},
{"id": "surface_to_air_missile", "name": "Surface-to-air missile", "year": 1953, "cat": "military", "wiki": "Surface-to-air missile", "req": ["radar", "rocket", "proximity_fuze"], "desc": "Radar-guided missiles such as Nike Ajax were deployed to shoot down bombers."},
{"id": "nuclear_submarine", "name": "Nuclear submarine", "year": 1954, "cat": "military", "wiki": "Nuclear submarine", "req": ["submarine", "nuclear_reactor"], "desc": "USS Nautilus, powered by a reactor, could stay submerged for weeks."},
{"id": "air_to_air_missile", "name": "Air-to-air missile", "year": 1956, "cat": "military", "wiki": "Air-to-air missile", "req": ["fighter_aircraft", "surface_to_air_missile"], "desc": "Guided missiles such as the infrared-homing Sidewinder became the main weapons of fighters."},
{"id": "anti_tank_guided_missile", "name": "Anti-tank guided missile", "year": 1956, "cat": "military", "wiki": "Anti-tank guided missile", "req": ["bazooka", "precision_guided_munition"], "desc": "Wire-guided missiles such as the French SS.10 let infantry destroy tanks at long range."},
{"id": "icbm", "name": "ICBM", "year": 1957, "cat": "military", "wiki": "Intercontinental ballistic missile", "req": ["ballistic_missile", "hydrogen_bomb"], "desc": "The Soviet R-7 was the first missile able to deliver a nuclear warhead between continents."},
{"id": "slbm", "name": "Submarine-launched ballistic missile", "year": 1960, "cat": "military", "wiki": "Submarine-launched ballistic missile", "req": ["ballistic_missile", "nuclear_submarine"], "desc": "The US Polaris missile was first fired from a submerged submarine in 1960."},
{"id": "ssbn", "name": "Ballistic missile submarine", "year": 1960, "cat": "military", "wiki": "Ballistic missile submarine", "req": ["slbm", "nuclear_submarine"], "desc": "USS George Washington began deterrent patrols in 1960, making nuclear forces survivable."},
{"id": "anti_ballistic_missile", "name": "Anti-ballistic missile", "year": 1961, "cat": "military", "wiki": "Anti-ballistic missile", "req": ["surface_to_air_missile", "icbm", "electronic_computer"], "desc": "A Soviet V-1000 interceptor destroyed a ballistic missile warhead in 1961, beginning missile defence."},
{"id": "laser_guided_bomb", "name": "Laser-guided bomb", "year": 1968, "cat": "military", "wiki": "Laser-guided bomb", "req": ["precision_guided_munition", "laser"], "desc": "Bombs homing on reflected laser light, such as Paveway, were used in Vietnam."},
{"id": "mirv", "name": "MIRV", "year": 1970, "cat": "military", "wiki": "Multiple independently targetable reentry vehicle", "req": ["icbm"], "desc": "Missiles carrying several separately aimed warheads, first deployed on the US Minuteman III."},
{"id": "bulletproof_vest", "name": "Kevlar body armour", "year": 1975, "cat": "military", "wiki": "Bulletproof vest", "req": ["flak_jacket", "kevlar"], "desc": "Soft vests of DuPont's Kevlar aramid fibre became standard police and military protection."},
{"id": "loitering_munition", "name": "Loitering munition", "year": 1989, "cat": "military", "wiki": "Loitering munition", "req": ["cruise_missile", "precision_guided_munition", "uav"], "desc": "Weapons that wait over a target area before striking, starting with the anti-radar IAI Harpy."},
{"id": "ucav", "name": "Unmanned combat aerial vehicle", "year": 2001, "cat": "military", "wiki": "Unmanned combat aerial vehicle", "req": ["precision_guided_munition", "satellite", "airplane", "gps", "uav"], "desc": "Armed remotely piloted aircraft, such as the Predator fitted with Hellfire missiles, entered combat in 2001."},
{"id": "cyberwarfare", "name": "Cyberwarfare", "year": 2007, "cat": "military", "wiki": "Cyberwarfare", "req": ["internet"], "desc": "State-linked attacks on Estonian networks in 2007 marked the emergence of cyberwarfare."},
{"id": "stuxnet", "name": "Stuxnet", "year": 2010, "cat": "military", "wiki": "Stuxnet", "req": ["cyberwarfare", "computer_worm"], "desc": "A computer worm that physically damaged Iranian uranium centrifuges, the first known cyberweapon of its kind."},
{"id": "directed_energy_weapon", "name": "Directed-energy weapon", "year": 2014, "cat": "military", "wiki": "Directed-energy weapon", "req": ["laser"], "desc": "The US Navy's Laser Weapon System was deployed on USS Ponce in 2014."},
{"id": "hypersonic_glide_vehicle", "name": "Hypersonic glide vehicle", "year": 2019, "cat": "military", "wiki": "Hypersonic glide vehicle", "req": ["icbm", "mirv"], "desc": "Manoeuvring warheads gliding at hypersonic speed, such as Russia's Avangard, entered service in 2019."},
{"id": "boomerang", "name": "Boomerang", "year": -20000, "cat": "military", "wiki": "Boomerang", "req": ["stone_tools"], "desc": "Curved throwing sticks used for hunting and fighting, the oldest found in Poland and Australia."},
{"id": "battle_axe", "name": "Battle axe", "year": -3000, "cat": "military", "wiki": "Battle axe", "req": ["stone_tools", "smelting"], "desc": "Axes designed for combat, made of stone and later bronze and iron, used across Eurasia."},
{"id": "lorica_segmentata", "name": "Lorica segmentata", "year": 9, "cat": "military", "wiki": "Lorica segmentata", "req": ["lamellar_armour", "iron_working"], "desc": "Roman legionary armour of articulated iron strips, an early form of segmented plate."},
{"id": "japanese_sword", "name": "Japanese sword", "year": 900, "cat": "military", "wiki": "Japanese sword", "req": ["steel", "iron_sword"], "desc": "Curved differentially hardened steel blades developed in Heian Japan."},
{"id": "halberd", "name": "Halberd", "year": 1300, "cat": "military", "wiki": "Halberd", "req": ["spear", "steel"], "desc": "A pole weapon combining axe blade, spike and hook, used by late medieval infantry."},
{"id": "caltrop", "name": "Caltrop", "year": -331, "cat": "military", "wiki": "Caltrop", "req": ["iron_working"], "desc": "Spiked devices scattered on the ground to lame horses and slow infantry."},
{"id": "repeating_crossbow", "name": "Repeating crossbow", "year": -400, "cat": "military", "wiki": "Repeating crossbow", "req": ["crossbow"], "desc": "Chinese crossbows with a magazine and lever that allowed rapid successive shots."},
{"id": "onager", "name": "Onager", "year": 353, "cat": "military", "wiki": "Onager (weapon)", "req": ["ballista"], "desc": "A late Roman single-armed torsion engine that lobbed stones in an arc."},
{"id": "bombard", "name": "Bombard", "year": 1380, "cat": "military", "wiki": "Bombard (weapon)", "req": ["cannon"], "desc": "Very large siege cannons that broke medieval walls, such as at Constantinople in 1453."},
{"id": "pistol", "name": "Pistol", "year": 1510, "cat": "military", "wiki": "Pistol", "req": ["wheellock"], "desc": "Small one-handed firearms made practical by the wheellock, adopted by cavalry."},
{"id": "shrapnel_shell", "name": "Shrapnel shell", "year": 1784, "cat": "military", "wiki": "Shrapnel shell", "req": ["howitzer"], "desc": "Henry Shrapnel's timed shell burst in the air to scatter balls over troops."},
{"id": "gun_turret", "name": "Gun turret", "year": 1862, "cat": "military", "wiki": "Gun turret", "req": ["ironclad"], "desc": "Rotating armoured gun mounts, used on USS Monitor, let warships aim without turning."},
{"id": "napalm", "name": "Napalm", "year": 1942, "cat": "military", "wiki": "Napalm", "req": ["oil_refining", "flamethrower"], "desc": "Gelled petroleum incendiary developed at Harvard, used in firebombing and later wars."},
{"id": "motte_and_bailey", "name": "Motte-and-bailey castle", "year": 950, "cat": "military", "wiki": "Motte-and-bailey castle", "req": ["defensive_wall"], "desc": "Earthwork mounds topped by timber keeps, spread across Europe by the Normans."},
{"id": "machine_gun", "name": "Machine gun", "year": 1884, "cat": "military", "wiki": "Machine gun", "req": ["maxim_gun"], "desc": "Fully automatic guns firing continuously while the trigger is held dominated the battlefields of the First World War."},
{"id": "anti_aircraft_gun", "name": "Anti-aircraft gun", "year": 1914, "cat": "military", "wiki": "Anti-aircraft warfare", "req": ["canon_de_75", "airplane"], "desc": "High-angle guns were adapted to shoot at aircraft from the First World War onward."},
{"id": "main_battle_tank", "name": "Main battle tank", "year": 1945, "cat": "military", "wiki": "Main battle tank", "req": ["tank"], "desc": "Tanks combining heavy armour, firepower and mobility, such as the Centurion, replaced specialized types."},
{"id": "reactive_armour", "name": "Reactive armour", "year": 1982, "cat": "military", "wiki": "Reactive armour", "req": ["shaped_charge", "tank"], "desc": "Explosive armour tiles disrupt incoming shaped-charge jets, first fielded by Israel in 1982."},
{"id": "sledge", "name": "Sledge", "year": -8000, "cat": "transport", "wiki": "Sled", "req": ["stone_tools", "cordage"], "desc": "A runner-borne platform dragged over snow, ice or ground; among the earliest land vehicles."},
{"id": "travois", "name": "Travois", "year": -5000, "cat": "transport", "wiki": "Travois", "req": ["cordage", "domestication_of_animals"], "desc": "Two poles dragged in a V by a dog or horse to carry loads without wheels."},
{"id": "pack_animal", "name": "Pack animal", "year": -4000, "cat": "transport", "wiki": "Pack animal", "req": ["domestication_of_animals"], "desc": "Donkeys, camels, llamas and horses loaded with goods, the backbone of overland trade."},
{"id": "corduroy_road", "name": "Corduroy road", "year": -3800, "cat": "transport", "wiki": "Corduroy road", "req": ["stone_tools"], "desc": "Logs laid across wet ground to make a passable track, as in Britain's Sweet Track."},
{"id": "wagon", "name": "Wagon", "year": -3400, "cat": "transport", "wiki": "Wagon", "req": ["cart"], "desc": "A four-wheeled load vehicle, carrying more than a two-wheeled cart."},
{"id": "horse_bit", "name": "Bit", "year": -3500, "cat": "transport", "wiki": "Bit (horse)", "req": ["horse_domestication", "cordage"], "desc": "A mouthpiece with reins that lets a rider or driver steer and stop a horse."},
{"id": "horseback_riding", "name": "Horseback riding", "year": -3000, "cat": "transport", "wiki": "Equestrianism", "req": ["horse_domestication", "horse_bit"], "desc": "Riding horses for travel, herding and war, which shrank distances on the steppe."},
{"id": "spoked_wheel", "name": "Spoked wheel", "year": -2000, "cat": "transport", "wiki": "Spoke", "req": ["wheel", "bronze"], "desc": "A light wheel of hub, spokes and rim that made fast vehicles possible."},
{"id": "wheelbarrow", "name": "Wheelbarrow", "year": -400, "cat": "transport", "wiki": "Wheelbarrow", "req": ["wheel", "lever"], "desc": "A single-wheeled hand cart that lets one person move heavy loads."},
{"id": "saddle", "name": "Saddle", "year": -700, "cat": "transport", "wiki": "Saddle", "req": ["horseback_riding"], "desc": "A padded seat on a horse's back that spreads the rider's weight and improves control."},
{"id": "stirrup", "name": "Stirrup", "year": 322, "cat": "transport", "wiki": "Stirrup", "req": ["saddle"], "desc": "Foot loops hung from the saddle that steady the rider; spread from China across Eurasia."},
{"id": "hipposandal", "name": "Hipposandal", "year": -100, "cat": "transport", "wiki": "Hipposandal", "req": ["horse_domestication", "iron_working"], "desc": "A Roman strapped-on iron sandal protecting horses' hooves on hard roads."},
{"id": "south_pointing_chariot", "name": "South-pointing chariot", "year": 235, "cat": "transport", "wiki": "South-pointing chariot", "req": ["gear", "chariot"], "desc": "A Chinese cart whose differential gearing kept a pointer facing one direction."},
{"id": "diolkos", "name": "Diolkos", "year": -600, "cat": "transport", "wiki": "Diolkos", "req": ["cart"], "desc": "A paved trackway with grooves for hauling ships across the Isthmus of Corinth."},
{"id": "roman_roads", "name": "Roman roads", "year": -312, "cat": "transport", "wiki": "Roman roads", "req": ["lime_mortar", "cart"], "desc": "Engineered, layered and drained roads that bound the Roman Empire together."},
{"id": "coach", "name": "Coach", "year": 1450, "cat": "transport", "wiki": "Coach (carriage)", "req": ["wagon", "cordage"], "desc": "A covered carriage with a suspended body, first built at Kocs in Hungary."},
{"id": "horsebus", "name": "Horse-drawn omnibus", "year": 1662, "cat": "transport", "wiki": "Horse-drawn omnibus", "req": ["coach"], "desc": "A large coach running a fixed route for paying passengers, the first public transit."},
{"id": "leaf_spring", "name": "Leaf spring", "year": 1804, "cat": "transport", "wiki": "Leaf spring", "req": ["steel", "coach"], "desc": "Stacked steel strips forming a spring that cushions vehicles from road shocks."},
{"id": "differential", "name": "Differential", "year": 1827, "cat": "transport", "wiki": "Differential (mechanical device)", "req": ["gear"], "desc": "A gear train letting wheels on one axle turn at different speeds when cornering."},
{"id": "reed_boat", "name": "Reed boat", "year": -5500, "cat": "transport", "wiki": "Reed boat", "req": ["cordage"], "desc": "Bundled reed hulls used on the Nile, in Mesopotamia and on Lake Titicaca."},
{"id": "sewn_boat", "name": "Plank boat", "year": -3000, "cat": "transport", "wiki": "Sewn boat", "req": ["dugout_canoe", "cordage", "smelting"], "desc": "Planked hulls stitched or pegged together, allowing larger ships than dugouts."},
{"id": "oar", "name": "Oar", "year": -3000, "cat": "transport", "wiki": "Oar", "req": ["dugout_canoe", "lever"], "desc": "A pole with a blade levered against the hull to row boats."},
{"id": "steering_oar", "name": "Steering oar", "year": -3000, "cat": "transport", "wiki": "Steering oar", "req": ["oar"], "desc": "A large oar at the stern used to steer ships before the rudder."},
{"id": "harbor", "name": "Harbor", "year": -2500, "cat": "transport", "wiki": "Harbor", "req": ["sewn_boat"], "desc": "A sheltered anchorage with quays, as at Wadi al-Jarf in Egypt."},
{"id": "outrigger_boat", "name": "Outrigger boat", "year": -1500, "cat": "transport", "wiki": "Outrigger boat", "req": ["dugout_canoe", "sail"], "desc": "A canoe stabilized by floats on booms, carrying Austronesians across oceans."},
{"id": "catamaran", "name": "Catamaran", "year": -1500, "cat": "transport", "wiki": "Catamaran", "req": ["dugout_canoe", "cordage"], "desc": "A twin-hulled vessel with great stability, developed by Austronesian seafarers."},
{"id": "crab_claw_sail", "name": "Crab claw sail", "year": -1500, "cat": "transport", "wiki": "Austronesian sail types", "req": ["sail"], "desc": "A triangular Austronesian sail giving strong lift for ocean voyaging."},
{"id": "polynesian_navigation", "name": "Polynesian navigation", "year": -1000, "cat": "transport", "wiki": "Polynesian navigation", "req": ["outrigger_boat"], "desc": "Wayfinding by stars, swells and birds that settled the remote Pacific."},
{"id": "galley", "name": "Galley", "year": -1500, "cat": "transport", "wiki": "Galley", "req": ["oar", "sewn_boat", "sail"], "desc": "A long ship propelled mainly by oars, dominant in the Mediterranean for millennia."},
{"id": "dry_dock", "name": "Dry dock", "year": -200, "cat": "transport", "wiki": "Dry dock", "req": ["harbor"], "desc": "A basin that can be drained to build or repair a ship's hull."},
{"id": "canal", "name": "Canal", "year": -600, "cat": "transport", "wiki": "Canal", "req": ["irrigation"], "desc": "An artificial waterway for navigation linking rivers and seas."},
{"id": "flash_lock", "name": "Flash lock", "year": -214, "cat": "transport", "wiki": "Flash lock", "req": ["canal"], "desc": "A removable barrier that releases a surge of water to carry boats past a weir."},
{"id": "grand_canal", "name": "Grand Canal", "year": 609, "cat": "transport", "wiki": "Grand Canal (China)", "req": ["canal", "flash_lock"], "desc": "The longest canal in the world, linking northern and southern China."},
{"id": "pound_lock", "name": "Pound lock", "year": 984, "cat": "transport", "wiki": "Lock (water navigation)", "req": ["flash_lock"], "desc": "A chamber with gates at both ends that raises or lowers boats between levels."},
{"id": "sternpost_rudder", "name": "Rudder", "year": 100, "cat": "transport", "wiki": "Rudder", "req": ["steering_oar"], "desc": "A hinged blade on the sternpost that steers large ships effectively."},
{"id": "junk", "name": "Junk", "year": 200, "cat": "transport", "wiki": "Junk (ship)", "req": ["sail", "sternpost_rudder"], "desc": "A Chinese sailing ship with battened sails and a stern rudder."},
{"id": "watertight_compartment", "name": "Watertight compartment", "year": 400, "cat": "transport", "wiki": "Compartment (ship)", "req": ["junk"], "desc": "Bulkheads dividing a hull so one breach does not sink the ship."},
{"id": "lateen_sail", "name": "Lateen sail", "year": 200, "cat": "transport", "wiki": "Lateen", "req": ["sail"], "desc": "A triangular fore-and-aft sail allowing ships to sail closer to the wind."},
{"id": "dhow", "name": "Dhow", "year": 600, "cat": "transport", "wiki": "Dhow", "req": ["lateen_sail", "sewn_boat"], "desc": "A lateen-rigged trading ship of the Indian Ocean and Red Sea."},
{"id": "clinker", "name": "Clinker construction", "year": 300, "cat": "transport", "wiki": "Clinker (boat building)", "req": ["sewn_boat", "iron_working"], "desc": "Overlapping planks riveted together, the hull method of northern Europe."},
{"id": "longship", "name": "Longship", "year": 790, "cat": "transport", "wiki": "Longship", "req": ["clinker", "sail", "oar"], "desc": "A long, shallow Viking ship under sail and oar, reaching from Vinland to Constantinople."},
{"id": "cog", "name": "Cog", "year": 1200, "cat": "transport", "wiki": "Cog (ship)", "req": ["clinker", "sail", "sternpost_rudder"], "desc": "A flat-bottomed, single-masted merchant ship of the Hanseatic League."},
{"id": "carvel", "name": "Carvel construction", "year": 1000, "cat": "transport", "wiki": "Carvel (boat building)", "req": ["sewn_boat", "iron_working"], "desc": "Frame-first hulls with flush planks, allowing larger and stronger ships."},
{"id": "portolan_chart", "name": "Portolan chart", "year": 1270, "cat": "transport", "wiki": "Portolan chart", "req": ["compass"], "desc": "Sea charts drawn from compass bearings and distances between ports."},
{"id": "carrack", "name": "Carrack", "year": 1400, "cat": "transport", "wiki": "Carrack", "req": ["cog", "carvel", "lateen_sail"], "desc": "A large three- or four-masted ocean ship that carried the voyages of exploration."},
{"id": "caravel", "name": "Caravel", "year": 1440, "cat": "transport", "wiki": "Caravel", "req": ["carvel", "lateen_sail", "sternpost_rudder"], "desc": "A small, nimble Portuguese ship able to sail upwind along African coasts."},
{"id": "full_rigged_ship", "name": "Full-rigged ship", "year": 1500, "cat": "transport", "wiki": "Full-rigged ship", "req": ["carrack"], "desc": "A ship with three or more square-rigged masts, the standard oceangoing vessel."},
{"id": "galleon", "name": "Galleon", "year": 1530, "cat": "transport", "wiki": "Galleon", "req": ["carrack"], "desc": "A large multi-decked sailing ship used for trade and war, as on the Manila route."},
{"id": "canal_du_midi", "name": "Canal du Midi", "year": 1681, "cat": "transport", "wiki": "Canal du Midi", "req": ["pound_lock"], "desc": "A summit-level canal linking the Atlantic and Mediterranean across France."},
{"id": "clipper", "name": "Clipper", "year": 1845, "cat": "transport", "wiki": "Clipper", "req": ["full_rigged_ship"], "desc": "A sharp-hulled, heavily canvassed sailing ship built for speed."},
{"id": "paddle_steamer", "name": "Paddle steamer", "year": 1783, "cat": "transport", "wiki": "Paddle steamer", "req": ["steam_engine"], "desc": "A vessel driven by steam-powered paddle wheels."},
{"id": "electric_boat", "name": "Electric boat", "year": 1839, "cat": "transport", "wiki": "Electric boat", "req": ["electric_motor", "voltaic_pile"], "desc": "A battery-powered boat, first demonstrated by Moritz von Jacobi on the Neva."},
{"id": "propeller", "name": "Screw propeller", "year": 1836, "cat": "transport", "wiki": "Propeller", "req": ["steamship", "screw"], "desc": "A rotating helical blade that drives ships more efficiently than paddles."},
{"id": "ss_great_britain", "name": "SS Great Britain", "year": 1843, "cat": "transport", "wiki": "SS Great Britain", "req": ["propeller", "iron_working"], "desc": "Brunel's iron-hulled, screw-driven ship, the forerunner of modern liners."},
{"id": "ocean_liner", "name": "Ocean liner", "year": 1838, "cat": "transport", "wiki": "Ocean liner", "req": ["steamship"], "desc": "A ship running scheduled passenger service across oceans."},
{"id": "roll_on_roll_off", "name": "Roll-on/roll-off ship", "year": 1850, "cat": "transport", "wiki": "Roll-on/roll-off", "req": ["steamship", "railway"], "desc": "Vessels that vehicles drive or roll onto, starting with railway train ferries."},
{"id": "bulk_carrier", "name": "Bulk carrier", "year": 1852, "cat": "transport", "wiki": "Bulk carrier", "req": ["steamship"], "desc": "A ship carrying unpackaged cargo such as coal, ore or grain in holds."},
{"id": "icebreaker", "name": "Icebreaker", "year": 1864, "cat": "transport", "wiki": "Icebreaker", "req": ["steamship"], "desc": "A ship with a strengthened hull that breaks ice to keep sea lanes open."},
{"id": "suez_canal", "name": "Suez Canal", "year": 1869, "cat": "transport", "wiki": "Suez Canal", "req": ["canal", "steamship"], "desc": "A sea-level canal joining the Mediterranean and Red Sea, shortening Europe to Asia routes."},
{"id": "oil_tanker", "name": "Oil tanker", "year": 1878, "cat": "transport", "wiki": "Oil tanker", "req": ["steamship", "oil_refining"], "desc": "A ship that carries oil in bulk in its hull tanks."},
{"id": "motorboat", "name": "Motorboat", "year": 1886, "cat": "transport", "wiki": "Motorboat", "req": ["internal_combustion_engine"], "desc": "A small boat driven by an internal combustion engine."},
{"id": "turbinia", "name": "Turbinia", "year": 1894, "cat": "transport", "wiki": "Turbinia", "req": ["propeller", "thermodynamics", "steam_turbine"], "desc": "The first steam turbine ship, far faster than any vessel of its day."},
{"id": "motor_ship", "name": "Motor ship", "year": 1903, "cat": "transport", "wiki": "Motor ship", "req": ["internal_combustion_engine", "steamship", "diesel_engine"], "desc": "A ship powered by a diesel engine rather than steam."},
{"id": "hydrofoil", "name": "Hydrofoil", "year": 1906, "cat": "transport", "wiki": "Hydrofoil", "req": ["motorboat", "aerodynamics"], "desc": "A boat lifted on underwater wings, cutting drag at speed."},
{"id": "panama_canal", "name": "Panama Canal", "year": 1914, "cat": "transport", "wiki": "Panama Canal", "req": ["pound_lock", "steamship", "electric_motor", "steam_shovel", "dynamite", "portland_cement"], "desc": "A lock canal across Panama joining the Atlantic and Pacific."},
{"id": "bathyscaphe", "name": "Bathyscaphe", "year": 1948, "cat": "transport", "wiki": "Bathyscaphe", "req": ["submarine"], "desc": "A free-diving deep-sea craft with a float and pressure sphere; Trieste reached the Challenger Deep in 1960."},
{"id": "nuclear_marine_propulsion", "name": "Nuclear marine propulsion", "year": 1955, "cat": "transport", "wiki": "Nuclear marine propulsion", "req": ["nuclear_reactor", "propeller"], "desc": "A shipboard reactor that lets vessels run for years without refueling."},
{"id": "ns_savannah", "name": "NS Savannah", "year": 1962, "cat": "transport", "wiki": "NS Savannah", "req": ["nuclear_marine_propulsion"], "desc": "The first nuclear-powered merchant ship."},
{"id": "intermodal_container", "name": "Intermodal container", "year": 1956, "cat": "transport", "wiki": "Intermodal container", "req": ["steel", "truck", "railway"], "desc": "A standard steel box moved between ship, rail and truck without unpacking."},
{"id": "container_ship", "name": "Container ship", "year": 1956, "cat": "transport", "wiki": "Container ship", "req": ["intermodal_container", "motor_ship"], "desc": "A ship built to carry intermodal containers, the engine of modern globalization."},
{"id": "container_crane", "name": "Container crane", "year": 1959, "cat": "transport", "wiki": "Container crane", "req": ["intermodal_container", "electric_motor"], "desc": "A dockside gantry crane that loads and unloads containers rapidly."},
{"id": "hovercraft", "name": "Hovercraft", "year": 1959, "cat": "transport", "wiki": "Hovercraft", "req": ["internal_combustion_engine", "aerodynamics"], "desc": "A vehicle riding on a cushion of air over land and water."},
{"id": "yara_birkeland", "name": "Yara Birkeland", "year": 2022, "cat": "transport", "wiki": "MV Yara Birkeland", "req": ["container_ship", "lithium_ion_battery", "self_driving_car"], "desc": "A battery-electric container ship designed for autonomous operation."},
{"id": "wagonway", "name": "Wagonway", "year": 1550, "cat": "transport", "wiki": "Wagonway", "req": ["cart"], "desc": "Wooden rails guiding horse-drawn wagons at mines, the ancestor of railways."},
{"id": "tram", "name": "Tram", "year": 1807, "cat": "transport", "wiki": "Tram", "req": ["wagonway"], "desc": "Street rail vehicles for passengers, first horse-drawn at Swansea."},
{"id": "rack_railway", "name": "Rack railway", "year": 1812, "cat": "transport", "wiki": "Rack railway", "req": ["steam_locomotive", "gear"], "desc": "A railway with a toothed rail engaging a cog to climb steep grades."},
{"id": "liverpool_manchester", "name": "Liverpool and Manchester Railway", "year": 1830, "cat": "transport", "wiki": "Liverpool and Manchester Railway", "req": ["railway", "stephensons_rocket"], "desc": "The first intercity railway relying entirely on steam locomotives."},
{"id": "bogie", "name": "Bogie", "year": 1832, "cat": "transport", "wiki": "Bogie", "req": ["railway"], "desc": "A pivoting wheeled truck that lets long rail vehicles take curves."},
{"id": "wire_rope", "name": "Wire rope", "year": 1834, "cat": "transport", "wiki": "Wire rope", "req": ["cordage", "iron_working"], "desc": "Twisted metal wires forming a strong cable for mines, cable cars and bridges."},
{"id": "railway_signal", "name": "Railway signal", "year": 1841, "cat": "transport", "wiki": "Railway signal", "req": ["railway"], "desc": "Fixed signals telling train drivers whether the line ahead is clear."},
{"id": "interlocking", "name": "Interlocking", "year": 1856, "cat": "transport", "wiki": "Interlocking", "req": ["railway_signal"], "desc": "Mechanisms preventing conflicting signal and switch settings."},
{"id": "funicular", "name": "Funicular", "year": 1862, "cat": "transport", "wiki": "Funicular", "req": ["wire_rope", "railway"], "desc": "A cable railway with counterbalanced cars on a steep slope."},
{"id": "rapid_transit", "name": "Rapid transit", "year": 1863, "cat": "transport", "wiki": "Rapid transit", "req": ["railway", "steam_locomotive"], "desc": "High-capacity urban railways on separated tracks, starting with London's Metropolitan Railway."},
{"id": "elevated_railway", "name": "Elevated railway", "year": 1868, "cat": "transport", "wiki": "Elevated railway", "req": ["rapid_transit", "cast_iron"], "desc": "Urban railways carried above streets on viaducts."},
{"id": "railway_air_brake", "name": "Railway air brake", "year": 1869, "cat": "transport", "wiki": "Railway air brake", "req": ["railway", "steam_engine"], "desc": "Westinghouse's compressed-air brake acting on every car of a train."},
{"id": "cable_car", "name": "Cable car", "year": 1873, "cat": "transport", "wiki": "Cable car (railway)", "req": ["wire_rope", "tram", "steam_engine"], "desc": "Streetcars gripping a moving underground cable, as in San Francisco."},
{"id": "electric_locomotive", "name": "Electric locomotive", "year": 1879, "cat": "transport", "wiki": "Electric locomotive", "req": ["electric_motor", "electric_generator", "railway"], "desc": "A locomotive powered by electricity, first demonstrated by Siemens in Berlin."},
{"id": "electric_tram", "name": "Electric tram", "year": 1881, "cat": "transport", "wiki": "Gross-Lichterfelde Tramway", "req": ["tram", "electric_locomotive"], "desc": "The world's first commercially successful electric tramway, in Berlin."},
{"id": "overhead_line", "name": "Overhead line", "year": 1881, "cat": "transport", "wiki": "Overhead line", "req": ["electric_tram"], "desc": "Wires above the track that feed power to trains, trams and trolleybuses."},
{"id": "regenerative_braking", "name": "Regenerative braking", "year": 1886, "cat": "transport", "wiki": "Regenerative braking", "req": ["electric_motor", "electric_generator"], "desc": "Braking by using a motor as a generator to recover energy."},
{"id": "third_rail", "name": "Third rail", "year": 1890, "cat": "transport", "wiki": "Third rail", "req": ["electric_locomotive"], "desc": "A conductor rail alongside the track supplying power to trains, first on London's deep tube."},
{"id": "multiple_unit", "name": "Multiple unit", "year": 1897, "cat": "transport", "wiki": "Multiple unit", "req": ["electric_locomotive"], "desc": "Self-propelled cars controlled together from one cab, standard for commuter trains."},
{"id": "monorail", "name": "Monorail", "year": 1901, "cat": "transport", "wiki": "Monorail", "req": ["electric_locomotive"], "desc": "A railway running on a single rail or beam, as on the Wuppertal Schwebebahn."},
{"id": "aerial_tramway", "name": "Aerial tramway", "year": 1907, "cat": "transport", "wiki": "Aerial tramway", "req": ["wire_rope", "electric_motor"], "desc": "Cabins suspended from cables carrying passengers up mountains."},
{"id": "diesel_locomotive", "name": "Diesel locomotive", "year": 1912, "cat": "transport", "wiki": "Diesel locomotive", "req": ["internal_combustion_engine", "railway", "electric_generator", "diesel_engine"], "desc": "A locomotive powered by a diesel engine, which replaced steam worldwide."},
{"id": "centralized_traffic_control", "name": "Centralized traffic control", "year": 1927, "cat": "transport", "wiki": "Centralized traffic control", "req": ["interlocking", "telegraph"], "desc": "Remote control of signals and switches over a whole line from one office."},
{"id": "high_speed_rail", "name": "High-speed rail", "year": 1964, "cat": "transport", "wiki": "High-speed rail", "req": ["electric_locomotive", "centralized_traffic_control", "multiple_unit"], "desc": "Dedicated lines and trains running above 200 km/h."},
{"id": "shinkansen", "name": "Shinkansen", "year": 1964, "cat": "transport", "wiki": "Shinkansen", "req": ["high_speed_rail"], "desc": "Japan's high-speed rail network, opened between Tokyo and Osaka."},
{"id": "automatic_train_operation", "name": "Automatic train operation", "year": 1967, "cat": "transport", "wiki": "Automatic train operation", "req": ["centralized_traffic_control", "transistor"], "desc": "Computer control of train driving, from London's Victoria line to driverless metros."},
{"id": "light_rail", "name": "Light rail", "year": 1978, "cat": "transport", "wiki": "Light rail", "req": ["electric_tram"], "desc": "Modern tram-like urban rail on partly segregated tracks."},
{"id": "maglev", "name": "Maglev", "year": 1984, "cat": "transport", "wiki": "Maglev", "req": ["electromagnet", "electric_motor", "high_speed_rail"], "desc": "Trains levitated and propelled by magnetic fields, with no wheel contact."},
{"id": "scmaglev", "name": "SCMaglev", "year": 1997, "cat": "transport", "wiki": "SCMaglev", "req": ["maglev", "superconducting_magnet", "niobium_titanium"], "desc": "Japan's superconducting maglev, which set the rail speed record of 603 km/h."},
{"id": "hydrogen_train", "name": "Hydrogen train", "year": 2018, "cat": "transport", "wiki": "Alstom Coradia LINT", "req": ["fuel_cell_vehicle", "railway", "pem_fuel_cell"], "desc": "The first passenger train powered by hydrogen fuel cells in regular service."},
{"id": "dandy_horse", "name": "Dandy horse", "year": 1817, "cat": "transport", "wiki": "Dandy horse", "req": ["spoked_wheel"], "desc": "Karl Drais's two-wheeled running machine, the first bicycle."},
{"id": "velocipede", "name": "Velocipede", "year": 1863, "cat": "transport", "wiki": "Velocipede", "req": ["dandy_horse", "iron_working"], "desc": "Pedal-driven bicycle with cranks on the front wheel."},
{"id": "wire_wheel", "name": "Wire wheel", "year": 1870, "cat": "transport", "wiki": "Wire wheel", "req": ["spoked_wheel", "steel"], "desc": "A light wheel with tensioned wire spokes."},
{"id": "penny_farthing", "name": "Penny-farthing", "year": 1871, "cat": "transport", "wiki": "Penny-farthing", "req": ["velocipede", "wire_wheel"], "desc": "A high-wheel bicycle with a large direct-drive front wheel."},
{"id": "safety_bicycle", "name": "Safety bicycle", "year": 1885, "cat": "transport", "wiki": "Safety bicycle", "req": ["penny_farthing", "roller_chain"], "desc": "A chain-driven bicycle with equal wheels, the form still used today."},
{"id": "pneumatic_tire", "name": "Pneumatic tire", "year": 1888, "cat": "transport", "wiki": "Tire", "req": ["vulcanization", "wire_wheel"], "desc": "An air-filled rubber tire that cushioned bicycles and later cars."},
{"id": "motorcycle", "name": "Motorcycle", "year": 1885, "cat": "transport", "wiki": "Motorcycle", "req": ["internal_combustion_engine", "velocipede", "four_stroke_engine", "carburetor"], "desc": "A two-wheeled motor vehicle, first built by Daimler and Maybach."},
{"id": "bicycle_sharing", "name": "Bicycle-sharing system", "year": 1965, "cat": "transport", "wiki": "Bicycle-sharing system", "req": ["safety_bicycle"], "desc": "Public bicycles available for short-term use, later automated with docks and apps."},
{"id": "electric_bicycle", "name": "Electric bicycle", "year": 1993, "cat": "transport", "wiki": "E-bike", "req": ["safety_bicycle", "electric_motor"], "desc": "A bicycle with a battery-powered motor assisting the rider."},
{"id": "fardier", "name": "Fardier à vapeur", "year": 1769, "cat": "transport", "wiki": "Nicolas-Joseph Cugnot", "req": ["steam_engine"], "desc": "Cugnot's steam tractor, the first self-propelled land vehicle."},
{"id": "electric_car", "name": "Electric car", "year": 1881, "cat": "transport", "wiki": "Electric car", "req": ["electric_motor", "voltaic_pile", "lead_acid_battery"], "desc": "A car powered by an electric motor and batteries, first by Gustave Trouvé."},
{"id": "carburetor", "name": "Carburetor", "year": 1885, "cat": "transport", "wiki": "Carburetor", "req": ["internal_combustion_engine"], "desc": "A device mixing fuel and air for gasoline engines."},
{"id": "manual_transmission", "name": "Manual transmission", "year": 1894, "cat": "transport", "wiki": "Manual transmission", "req": ["automobile", "gear"], "desc": "A driver-shifted gearbox matching engine speed to road speed."},
{"id": "bus", "name": "Bus", "year": 1895, "cat": "transport", "wiki": "Bus", "req": ["automobile", "horsebus"], "desc": "A motor vehicle carrying many passengers on fixed routes."},
{"id": "truck", "name": "Truck", "year": 1896, "cat": "transport", "wiki": "Truck", "req": ["automobile"], "desc": "A motor vehicle built to carry freight."},
{"id": "taxicab", "name": "Taxicab", "year": 1897, "cat": "transport", "wiki": "Taxi", "req": ["automobile"], "desc": "A car for hire with a driver, charging by meter."},
{"id": "semi_trailer_truck", "name": "Semi-trailer truck", "year": 1899, "cat": "transport", "wiki": "Semi-trailer truck", "req": ["truck"], "desc": "A tractor unit hauling a detachable semi-trailer, the main freight carrier on roads."},
{"id": "hybrid_vehicle", "name": "Hybrid electric vehicle", "year": 1900, "cat": "transport", "wiki": "Hybrid electric vehicle", "req": ["electric_car", "internal_combustion_engine"], "desc": "A vehicle combining an engine and electric drive, from Lohner-Porsche to the Prius."},
{"id": "continuous_track", "name": "Continuous track", "year": 1901, "cat": "transport", "wiki": "Continuous track", "req": ["steam_engine", "wagon"], "desc": "An endless band of plates spreading a vehicle's weight over soft ground."},
{"id": "drum_brake", "name": "Drum brake", "year": 1902, "cat": "transport", "wiki": "Drum brake", "req": ["automobile"], "desc": "Shoes pressing outward against a rotating drum to slow a wheel."},
{"id": "disc_brake", "name": "Disc brake", "year": 1902, "cat": "transport", "wiki": "Disc brake", "req": ["automobile"], "desc": "Pads clamping a rotating disc, giving strong, fade-resistant braking."},
{"id": "spark_plug", "name": "Spark plug", "year": 1902, "cat": "transport", "wiki": "Spark plug", "req": ["internal_combustion_engine", "transformer"], "desc": "A plug firing a high-voltage spark to ignite fuel in an engine cylinder."},
{"id": "filling_station", "name": "Filling station", "year": 1905, "cat": "transport", "wiki": "Filling station", "req": ["automobile", "oil_refining"], "desc": "A roadside facility selling fuel to motorists."},
{"id": "model_t", "name": "Ford Model T", "year": 1908, "cat": "transport", "wiki": "Ford Model T", "req": ["automobile", "interchangeable_parts"], "desc": "The cheap, durable car that made motoring a mass phenomenon."},
{"id": "electric_starter", "name": "Electric starter", "year": 1911, "cat": "transport", "wiki": "Starter (engine)", "req": ["electric_motor", "automobile"], "desc": "An electric motor that cranks the engine, ending hand cranking."},
{"id": "hydraulic_brake", "name": "Hydraulic brake", "year": 1918, "cat": "transport", "wiki": "Hydraulic brake", "req": ["drum_brake"], "desc": "Brakes actuated by fluid pressure, applying even force at every wheel."},
{"id": "turbocharger", "name": "Turbocharger", "year": 1925, "cat": "transport", "wiki": "Turbocharger", "req": ["internal_combustion_engine", "gas_turbine"], "desc": "An exhaust-driven turbine compressor that boosts engine power."},
{"id": "automatic_transmission", "name": "Automatic transmission", "year": 1939, "cat": "transport", "wiki": "Automatic transmission", "req": ["manual_transmission"], "desc": "A gearbox that shifts by itself, first mass-produced as GM's Hydra-Matic."},
{"id": "seat_belt", "name": "Seat belt", "year": 1949, "cat": "transport", "wiki": "Seat belt", "req": ["automobile"], "desc": "A harness holding occupants in place in a crash; the three-point belt came in 1959."},
{"id": "crumple_zone", "name": "Crumple zone", "year": 1952, "cat": "transport", "wiki": "Crumple zone", "req": ["automobile", "classical_mechanics"], "desc": "Car body sections designed to deform and absorb crash energy."},
{"id": "fuel_injection", "name": "Fuel injection", "year": 1955, "cat": "transport", "wiki": "Fuel injection", "req": ["carburetor"], "desc": "Metered injection of fuel into engine cylinders or intakes."},
{"id": "fuel_cell_vehicle", "name": "Fuel cell vehicle", "year": 1966, "cat": "transport", "wiki": "Fuel cell vehicle", "req": ["electric_car", "modern_chemistry", "alkaline_fuel_cell"], "desc": "A vehicle powered by a hydrogen fuel cell driving an electric motor."},
{"id": "engine_control_unit", "name": "Engine control unit", "year": 1968, "cat": "transport", "wiki": "Engine control unit", "req": ["fuel_injection", "integrated_circuit"], "desc": "An electronic computer managing fuel, ignition and emissions."},
{"id": "airbag", "name": "Airbag", "year": 1973, "cat": "transport", "wiki": "Airbag", "req": ["seat_belt", "modern_chemistry"], "desc": "A cushion that inflates in a crash to protect occupants."},
{"id": "catalytic_converter", "name": "Catalytic converter", "year": 1975, "cat": "transport", "wiki": "Catalytic converter", "req": ["automobile", "modern_chemistry"], "desc": "An exhaust device that turns pollutants into less harmful gases."},
{"id": "abs", "name": "Anti-lock braking system", "year": 1978, "cat": "transport", "wiki": "Anti-lock braking system", "req": ["hydraulic_brake", "microprocessor"], "desc": "Electronic control that stops wheels locking under hard braking."},
{"id": "car_navigation", "name": "Automotive navigation system", "year": 1990, "cat": "transport", "wiki": "Automotive navigation system", "req": ["satellite", "microprocessor", "automobile", "gps"], "desc": "In-car route guidance using satellite positioning and digital maps."},
{"id": "electronic_stability_control", "name": "Electronic stability control", "year": 1995, "cat": "transport", "wiki": "Electronic stability control", "req": ["abs"], "desc": "Braking individual wheels automatically to prevent skids."},
{"id": "adaptive_cruise_control", "name": "Adaptive cruise control", "year": 1995, "cat": "transport", "wiki": "Adaptive cruise control", "req": ["cruise_control", "radar", "microprocessor"], "desc": "Cruise control that keeps a safe gap to the vehicle ahead."},
{"id": "toyota_prius", "name": "Toyota Prius", "year": 1997, "cat": "transport", "wiki": "Toyota Prius", "req": ["hybrid_vehicle", "microprocessor", "nimh_battery"], "desc": "The first mass-produced hybrid car."},
{"id": "battery_electric_vehicle", "name": "Battery electric vehicle", "year": 2008, "cat": "transport", "wiki": "Battery electric vehicle", "req": ["electric_car", "lithium_ion_battery"], "desc": "A vehicle running solely on lithium-ion batteries, now a mass market."},
{"id": "self_driving_car", "name": "Self-driving car", "year": 1987, "cat": "transport", "wiki": "Self-driving car", "req": ["automobile", "electronic_computer", "artificial_intelligence", "computer_vision"], "desc": "A car that senses its surroundings and drives itself, first demonstrated in the 1980s."},
{"id": "ride_hailing", "name": "Ride-hailing", "year": 2009, "cat": "transport", "wiki": "Ridesharing company", "req": ["smartphone", "taxicab", "satellite", "gps"], "desc": "App-based services matching passengers with drivers in real time."},
{"id": "robotaxi", "name": "Robotaxi", "year": 2020, "cat": "transport", "wiki": "Robotaxi", "req": ["self_driving_car", "ride_hailing"], "desc": "Driverless taxis carrying paying passengers without a safety driver."},
{"id": "trolleybus", "name": "Trolleybus", "year": 1882, "cat": "transport", "wiki": "Trolleybus", "req": ["electric_motor", "overhead_line"], "desc": "An electric bus drawing power from twin overhead wires."},
{"id": "bus_rapid_transit", "name": "Bus rapid transit", "year": 1974, "cat": "transport", "wiki": "Bus rapid transit", "req": ["bus"], "desc": "Buses on dedicated lanes with stations, as pioneered in Curitiba."},
{"id": "radial_tire", "name": "Radial tire", "year": 1946, "cat": "transport", "wiki": "Radial tire", "req": ["pneumatic_tire", "steel"], "desc": "A tire with cords running across the tread, longer-lasting and safer."},
{"id": "macadam", "name": "Macadam", "year": 1820, "cat": "transport", "wiki": "Macadam", "req": ["roman_roads"], "desc": "Roads of compacted layers of broken stone, devised by John McAdam."},
{"id": "asphalt_concrete", "name": "Asphalt concrete", "year": 1870, "cat": "transport", "wiki": "Asphalt concrete", "req": ["macadam", "oil_refining"], "desc": "Aggregate bound with bitumen, the most common road surface."},
{"id": "tarmac", "name": "Tarmac", "year": 1902, "cat": "transport", "wiki": "Tarmacadam", "req": ["macadam", "coke_fuel"], "desc": "Macadam bound with tar, patented by Edgar Purnell Hooley."},
{"id": "traffic_light", "name": "Traffic light", "year": 1868, "cat": "transport", "wiki": "Traffic light", "req": ["railway_signal"], "desc": "Signals controlling traffic at intersections; electric versions from 1912."},
{"id": "road_marking", "name": "Road surface marking", "year": 1911, "cat": "transport", "wiki": "Road surface marking", "req": ["automobile", "asphalt_concrete"], "desc": "Painted lines and symbols guiding traffic on the road surface."},
{"id": "controlled_access_highway", "name": "Controlled-access highway", "year": 1924, "cat": "transport", "wiki": "Controlled-access highway", "req": ["automobile", "asphalt_concrete"], "desc": "A divided highway without at-grade crossings, from Italy's autostrade."},
{"id": "parking_meter", "name": "Parking meter", "year": 1935, "cat": "transport", "wiki": "Parking meter", "req": ["automobile", "mechanical_clock"], "desc": "A coin-operated timer charging for kerbside parking."},
{"id": "interstate_highway", "name": "Interstate Highway System", "year": 1956, "cat": "transport", "wiki": "Interstate Highway System", "req": ["controlled_access_highway"], "desc": "The US national network of controlled-access highways."},
{"id": "ski", "name": "Ski", "year": -6000, "cat": "transport", "wiki": "Ski", "req": ["stone_tools"], "desc": "Long wooden runners strapped to the feet for gliding over snow."},
{"id": "snowshoe", "name": "Snowshoe", "year": -4000, "cat": "transport", "wiki": "Snowshoe", "req": ["cordage"], "desc": "A wide frame worn on the foot to spread weight and walk on deep snow."},
{"id": "dog_sled", "name": "Dog sled", "year": -7000, "cat": "transport", "wiki": "Dog sled", "req": ["sledge", "domestication_of_animals"], "desc": "A sled hauled by teams of dogs, enabling travel and freight across Arctic regions."},
{"id": "kayak", "name": "Kayak", "year": -2000, "cat": "transport", "wiki": "Kayak", "req": ["cordage", "stone_tools"], "desc": "A narrow skin-covered Arctic boat paddled with a double-bladed paddle."},
{"id": "stagecoach", "name": "Stagecoach", "year": 1610, "cat": "transport", "wiki": "Stagecoach", "req": ["coach"], "desc": "Coaches running scheduled long-distance stages with fresh horses at each stop."},
{"id": "ackermann_steering", "name": "Ackermann steering geometry", "year": 1817, "cat": "transport", "wiki": "Ackermann steering geometry", "req": ["coach", "geometry"], "desc": "A linkage letting inner and outer wheels turn at different angles on a curve."},
{"id": "pulled_rickshaw", "name": "Rickshaw", "year": 1869, "cat": "transport", "wiki": "Pulled rickshaw", "req": ["spoked_wheel"], "desc": "A light two-wheeled cart pulled by a runner, widespread in Asian cities."},
{"id": "bireme", "name": "Bireme", "year": -700, "cat": "transport", "wiki": "Bireme", "req": ["galley"], "desc": "A galley with two banks of oars, used by Phoenicians and Greeks."},
{"id": "knarr", "name": "Knarr", "year": 900, "cat": "transport", "wiki": "Knarr", "req": ["clinker", "sail"], "desc": "A broad Norse cargo ship that carried settlers to Iceland and Greenland."},
{"id": "fluyt", "name": "Fluyt", "year": 1595, "cat": "transport", "wiki": "Fluyt", "req": ["full_rigged_ship"], "desc": "A cheap, capacious Dutch cargo ship that underpinned Dutch trade dominance."},
{"id": "gaff_rig", "name": "Gaff rig", "year": 1600, "cat": "transport", "wiki": "Gaff rig", "req": ["lateen_sail"], "desc": "A four-sided fore-and-aft sail set from a spar, efficient with small crews."},
{"id": "schooner", "name": "Schooner", "year": 1713, "cat": "transport", "wiki": "Schooner", "req": ["gaff_rig"], "desc": "A fast fore-and-aft rigged ship with two or more masts."},
{"id": "copper_sheathing", "name": "Copper sheathing", "year": 1761, "cat": "transport", "wiki": "Copper sheathing", "req": ["full_rigged_ship", "smelting"], "desc": "Copper plating on hulls to stop shipworm and fouling, making ships faster."},
{"id": "bridgewater_canal", "name": "Bridgewater Canal", "year": 1761, "cat": "transport", "wiki": "Bridgewater Canal", "req": ["canal"], "desc": "A coal canal that cut transport costs and launched Britain's canal age."},
{"id": "windjammer", "name": "Windjammer", "year": 1870, "cat": "transport", "wiki": "Windjammer", "req": ["clipper", "bessemer_process"], "desc": "A large iron- or steel-hulled sailing cargo ship of the late sail era."},
{"id": "ship_model_basin", "name": "Ship model basin", "year": 1872, "cat": "transport", "wiki": "Ship model basin", "req": ["classical_mechanics"], "desc": "A towing tank where scale models predict hull resistance, pioneered by William Froude."},
{"id": "boat_lift", "name": "Boat lift", "year": 1875, "cat": "transport", "wiki": "Boat lift", "req": ["pound_lock", "steam_engine"], "desc": "A machine that raises boats between canal levels in water-filled caissons."},
{"id": "outboard_motor", "name": "Outboard motor", "year": 1907, "cat": "transport", "wiki": "Outboard motor", "req": ["motorboat"], "desc": "A detachable engine and propeller unit clamped to a boat's stern."},
{"id": "bulbous_bow", "name": "Bulbous bow", "year": 1912, "cat": "transport", "wiki": "Bulbous bow", "req": ["ship_model_basin"], "desc": "A bulb below a ship's waterline that reduces wave-making drag."},
{"id": "rotor_ship", "name": "Rotor ship", "year": 1924, "cat": "transport", "wiki": "Rotor ship", "req": ["motor_ship", "classical_mechanics"], "desc": "A ship using spinning Flettner rotors and the Magnus effect for thrust."},
{"id": "pump_jet", "name": "Pump-jet", "year": 1954, "cat": "transport", "wiki": "Pump-jet", "req": ["internal_combustion_engine", "propeller"], "desc": "A ducted water jet propulsor for shallow-draft and fast craft."},
{"id": "auv", "name": "Autonomous underwater vehicle", "year": 1957, "cat": "transport", "wiki": "Autonomous underwater vehicle", "req": ["submarine", "vacuum_tube"], "desc": "An untethered robotic submarine that runs preprogrammed missions."},
{"id": "rov", "name": "Remotely operated underwater vehicle", "year": 1961, "cat": "transport", "wiki": "Remotely operated underwater vehicle", "req": ["submarine", "television"], "desc": "A tethered robot submarine controlled from the surface."},
{"id": "ais", "name": "Automatic identification system", "year": 2002, "cat": "transport", "wiki": "Automatic identification system", "req": ["radio", "satellite", "microprocessor", "gps"], "desc": "Ship transponders broadcasting position and identity to prevent collisions."},
{"id": "stephensons_rocket", "name": "Stephenson's Rocket", "year": 1829, "cat": "transport", "wiki": "Stephenson's Rocket", "req": ["steam_locomotive"], "desc": "The multitube-boiler locomotive that won the Rainhill Trials."},
{"id": "sleeping_car", "name": "Sleeping car", "year": 1857, "cat": "transport", "wiki": "Sleeping car", "req": ["railway", "bogie"], "desc": "A railway carriage with berths for overnight travel."},
{"id": "road_roller", "name": "Road roller", "year": 1863, "cat": "transport", "wiki": "Road roller", "req": ["traction_engine", "macadam"], "desc": "A heavy roller that compacts road surfaces, first steam-powered."},
{"id": "transcontinental_railroad", "name": "First transcontinental railroad", "year": 1869, "cat": "transport", "wiki": "First transcontinental railroad", "req": ["railway", "telegraph"], "desc": "The line linking the US east and west coasts."},
{"id": "janney_coupler", "name": "Janney coupler", "year": 1873, "cat": "transport", "wiki": "Janney coupler", "req": ["railway"], "desc": "An automatic knuckle coupler that made joining rail cars safer."},
{"id": "city_south_london", "name": "City and South London Railway", "year": 1890, "cat": "transport", "wiki": "City and South London Railway", "req": ["rapid_transit", "third_rail", "electric_locomotive"], "desc": "The first deep-level electric underground railway."},
{"id": "chairlift", "name": "Chairlift", "year": 1936, "cat": "transport", "wiki": "Chairlift", "req": ["aerial_tramway"], "desc": "Open chairs on a moving cable loop, carrying skiers uphill."},
{"id": "gas_turbine_locomotive", "name": "Gas turbine locomotive", "year": 1941, "cat": "transport", "wiki": "Gas-turbine locomotive", "req": ["gas_turbine", "railway"], "desc": "A locomotive powered by a gas turbine driving generators."},
{"id": "tilting_train", "name": "Tilting train", "year": 1973, "cat": "transport", "wiki": "Tilting train", "req": ["multiple_unit"], "desc": "Trains that lean into curves so they can run faster on existing track."},
{"id": "personal_rapid_transit", "name": "Personal rapid transit", "year": 1975, "cat": "transport", "wiki": "Personal rapid transit", "req": ["automatic_train_operation"], "desc": "Small automated pods on guideways, first at Morgantown, West Virginia."},
{"id": "tgv", "name": "TGV", "year": 1981, "cat": "transport", "wiki": "TGV", "req": ["high_speed_rail"], "desc": "France's high-speed train, holder of the conventional rail speed record."},
{"id": "shanghai_maglev", "name": "Shanghai maglev", "year": 2004, "cat": "transport", "wiki": "Shanghai maglev train", "req": ["maglev"], "desc": "The first commercial high-speed maglev line."},
{"id": "derailleur", "name": "Derailleur gears", "year": 1905, "cat": "transport", "wiki": "Derailleur", "req": ["safety_bicycle"], "desc": "Multiple sprockets and a chain-shifting mechanism for bicycle gearing."},
{"id": "motor_scooter", "name": "Motor scooter", "year": 1915, "cat": "transport", "wiki": "Scooter (motorcycle)", "req": ["motorcycle"], "desc": "A step-through motorcycle with small wheels, popularized by the Vespa."},
{"id": "scooter_sharing", "name": "Scooter-sharing system", "year": 2017, "cat": "transport", "wiki": "Scooter-sharing system", "req": ["bicycle_sharing", "lithium_ion_battery", "smartphone", "gps"], "desc": "App-rented dockless electric scooters in cities."},
{"id": "speedometer", "name": "Speedometer", "year": 1888, "cat": "transport", "wiki": "Speedometer", "req": ["odometer", "automobile"], "desc": "An instrument showing a vehicle's speed."},
{"id": "headlamp", "name": "Headlamp", "year": 1898, "cat": "transport", "wiki": "Headlamp", "req": ["automobile", "light_bulb"], "desc": "Lamps lighting the road ahead of a vehicle."},
{"id": "shock_absorber", "name": "Shock absorber", "year": 1901, "cat": "transport", "wiki": "Shock absorber", "req": ["leaf_spring", "automobile"], "desc": "A damper that controls spring motion for a smooth, stable ride."},
{"id": "windshield_wiper", "name": "Windshield wiper", "year": 1903, "cat": "transport", "wiki": "Windscreen wiper", "req": ["automobile"], "desc": "A blade sweeping rain from a vehicle's windscreen."},
{"id": "four_wheel_drive", "name": "Four-wheel drive", "year": 1903, "cat": "transport", "wiki": "Four-wheel drive", "req": ["automobile", "differential"], "desc": "Driving all four wheels for traction off-road and in snow."},
{"id": "car_radio", "name": "Car radio", "year": 1930, "cat": "transport", "wiki": "Vehicle audio", "req": ["radio", "automobile"], "desc": "A radio receiver built into a car."},
{"id": "snowmobile", "name": "Snowmobile", "year": 1935, "cat": "transport", "wiki": "Snowmobile", "req": ["continuous_track", "internal_combustion_engine", "ski"], "desc": "A tracked motor vehicle on skis for travel over snow."},
{"id": "power_steering", "name": "Power steering", "year": 1951, "cat": "transport", "wiki": "Power steering", "req": ["automobile"], "desc": "Hydraulic or electric assistance that reduces steering effort."},
{"id": "cruise_control", "name": "Cruise control", "year": 1958, "cat": "transport", "wiki": "Cruise control", "req": ["automobile"], "desc": "A system holding a car at a set speed without the driver's foot."},
{"id": "cvt", "name": "Continuously variable transmission", "year": 1958, "cat": "transport", "wiki": "Continuously variable transmission", "req": ["automatic_transmission"], "desc": "A transmission with infinitely variable ratios, first sold in DAF cars."},
{"id": "electronic_toll_collection", "name": "Electronic toll collection", "year": 1986, "cat": "transport", "wiki": "Electronic toll collection", "req": ["radio", "microprocessor"], "desc": "Radio tags that let vehicles pay tolls without stopping."},
{"id": "lane_departure_warning", "name": "Lane departure warning system", "year": 2000, "cat": "transport", "wiki": "Lane departure warning system", "req": ["automobile", "microprocessor", "television", "computer_vision"], "desc": "Cameras that warn a driver drifting out of lane."},
{"id": "darpa_grand_challenge", "name": "DARPA Grand Challenge", "year": 2004, "cat": "transport", "wiki": "DARPA Grand Challenge", "req": ["self_driving_car", "laser", "gps", "lidar"], "desc": "Robot vehicle races that catalysed modern autonomous driving."},
{"id": "plug_in_hybrid", "name": "Plug-in hybrid", "year": 2008, "cat": "transport", "wiki": "Plug-in hybrid", "req": ["hybrid_vehicle", "lithium_ion_battery"], "desc": "A hybrid whose battery can be charged from the grid for electric-only driving."},
{"id": "roundabout", "name": "Roundabout", "year": 1907, "cat": "transport", "wiki": "Roundabout", "req": ["automobile"], "desc": "A circular intersection where traffic flows around a central island."},
{"id": "cloverleaf_interchange", "name": "Cloverleaf interchange", "year": 1929, "cat": "transport", "wiki": "Cloverleaf interchange", "req": ["controlled_access_highway"], "desc": "A two-level junction with loop ramps eliminating left turns across traffic."},
{"id": "cats_eye", "name": "Cat's eye", "year": 1934, "cat": "transport", "wiki": "Cat's eye (road)", "req": ["road_marking", "glass"], "desc": "Retroreflecting road studs that mark lanes at night."}
]