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Want to know how your earbuds make music, how telephones squeeze sounds down wires, why broadband is faster than dialup, or how science can make you happy? You've come to the right place!

Hard stuff... made simple!

Explain that Stuff is a collection of around 360 completely free, easy-to-understand articles (and about 1700 photos and artworks), covering how things work, cutting-edge science, cool gadgets, and computers. Our mission is to explain things simply and clearly so you understand them completely.

There's more information on this website than in your average expensive science book—and it's all completely free to use! (Our photos and artworks are also free for you to reuse in school reports, science fair projects, and for other noncommercial uses under a Creative Commons license.)

Most read

These are our top-ten most-read articles:

  1. Global warming: Why is the world getting hotter and what can we do about it? What will be the consequences for humankind and the rest of the living world?
  2. Electricity: The most versatile and useful form of energy in our world, electricity is going to become a whole lot more important in future.
  3. Wireless Internet: Who can still remember the time when everyone had to connect to the Net very slowly through a piece of copper wire? How exactly does Wi-Fi work?
  4. Water pollution: Rivers and seas take a long time to recover from the effects of careless human treatment. What causes pollution and what can we do to stop it?
  5. Solar cells: Imagine being able to make electricity for free from nothing but sunlight! That's the promise of solar electricity, likely to be one of the most important forms of energy in the coming decades.
  6. Halogen cooktops: Can you boil an egg with nothing but light? Hi-tech halogen cooktops are convenient and easy-to-clean, but how exactly do they work?
  7. Power plants: We wouldn't be able to do much without power plants buzzing away in the background making our electricity, but we've only had these remarkable energy factories for just over 100 years!
  8. Air pollution: Doing a school or college project on pollution? Here's a comprehensive list of resources to help you get started.
  9. Hydraulics: What do water pistols have to do with cranes and diggers? They use hydraulics to give you more force at your fingertips.
  10. Jackhammers: Pneumatic drills that break up the road aren't powered by gasoline or even electricity: they're driven by nothing but tightly squeezed (compressed) air. Here's how they work!

More popular articles...

What else is on our site?

rss feedWe're adding new articles all the time, so do keep popping back! If you use RSS, you can use our articles feed to find out about new pages as soon as we publish them. Here's what's on the site so far:

Communications
Communications: Antennas and transmitters, Bluetooth, Broadband Internet, BPL (Broadband over power lines), Cellphones (Mobile phones), Data-matrix codes, Directional loudspeakers, Fax machines, Fiber optics, Internet, Headphones, Headphones (repairing), Hearing aids, Lenticular printing, Loudspeakers, LP record players, Microphones, Mobile broadband, Modems, Pagers, Radar, Radio, RFID tags, Streaming media, Telephones, Touchscreens, Ultrasound, Wireless Internet, World Wide Web...
Computers
Computers: Beginner's guide, BitTorrent, Cloud computing, How computers work, Computer mice, Computer networks, Encryption, Fingerprint scanners, Hard drives, History of computers, Integrated circuits, Keyboards, Linux, One Laptop Per Child (OLPC), RSS, Scanners, Spam, USB, Voice recognition software, Virtual reality, Webcams, Websites, Website testing with PHP...
Science
Electricity: Amplifiers, Batteries, Battery chargers, Capacitors, CHP cogeneration, Electricity, Electrolyzers, Electronics, Electrical energy monitors, Diodes and LEDs, Electric motors, Filament lamps, Fuses, Generators, Hub motors, Induction chargers, Inverters, Lithium-ion batteries, Nuclear power plants, OLEDs (organic LEDs) and LEPs (light-emitting polymers), Piezoelectricity, Power plants, RCD circuit breakers, Reed switches, Relays, Resistors, Strobe lights, Supercapacitors, Surge protectors, Transformers, Transistors, Xenon lamps...
Transport
Engineering: Bridges, Buildings, Carburetors, Engines, Gears, Hydraulics, Micro-wind turbines, Pumps and compressors, Springs, Tunnels, Turbines, Valves, Wind turbines...
environment
Environment: Air pollution, Biofuels, Carbon capture and storage (CCS), Carbon offsets, Earthquakes, Eco-homes, Electrostatic smoke precipitators, Fair trade, Geoengineering, Global warming and climate change, Greywater, Hydroponics, Nuclear power, Organic food and farming, Public attitudes, Rainforests, Renewable energy, Rivers, Recycling, Solar hot-water systems, Water pollution...
Technology
Gadgets: Blu-ray, Calculators, Cameras and digital cameras, Digital cameras (what's inside?), Camcorders, CCDs, CDs and DVDs, Digital pens, Digital radio, DLP® TV projectors, Electronic books (e-books), Electric guitars, External sound cards, Flash memory, Flatscreen television, GPS satellite navigation, HDTV (high-definition television), Logic gates, MP3 players, Nabaztag Wi-Fi rabbits, Plasma television, Projection television, Noise-cancelling headphones, Solar cells, Synthesizers, Yo-yos...
Household
Household: Aerosol cans, Air conditioners, Baby-monitors and intercoms, Blister plasters, Dehumidifiers, Electric showers, Electric toothbrushes, Energy-saving fluorescent lamps, Gas central heating boilers, HEPA filters, Heat pumps, Insulation, Intruder (burglar) alarms, Locks, LPG (liquified petroleum gas), Memory foam mattresses, Pressure washers, Remote control, Security marking, Smart homes, Smoke detectors, Sunscreen, Television, Toilets...
Instruments
Instruments and measurements: Accelerometers, Anemometers, Barometers, Blood-pressure monitors, Carbon monoxide detectors, Defibrillators, Dynamometers, Geiger counters, Hall-effect sensors, Hygrometers, Interferometers, Iris scanners, Metal detectors, Moving-coil meters, Oscilloscopes, pH meters, Pyranometers, Pyrometers, Quartz clocks and watches, Radio-controlled clocks (RCCs), Sound level (decibel) meters, Speedometers, Strain gauges, Thermometers, Thermostats, Thermocouples, Weather stations, Weights and balances, X rays...
Kitchen
Kitchen: Breadmaking machines, Coffee (pod) makers, Detergents, Dishwashers, Halogen cooking hobs, Microfiber cleaning cloths, Microwave ovens, Pressure cookers, Teflon® nonstick pans, Pasteurization, Refrigerators, Smoke detectors, Toasters, Vacuum cleaners, Vacuum flasks, Clothes washers (washing machines), Water filters...
Leisure and recreation
Leisure: Fireworks, Jet Ski® and Sea-Doo®, Neon lamps, Photochromic lenses, Pianos, Rollercoasters, Scuba diving, Surfing, Waterproof outdoor clothing, Wetsuits...
Materials
Materials: Adhesives, Alloys, Aluminum, Anti-static coatings, Biomimetic clothing, Bioplastics, Bricks, Bulletproof glass, Ceramics, Cermets, Chromium, Composites, Copper, Dry-stone walls, Electroplating, Energy-absorbing plastics, Glass, Gold, Iron and steel, GORE-TEX®, Kevlar®, Laminates, Lead, Lubricants, Molecular beam epitaxy, Nickel, Nomex®, Paint, Paper, Plastics, Platinum, Protective materials, Reinforced concrete, Rubber, Silver, Tin, Titanium, Tungsten, Water, Zinc...
Office
Office: Barcode scanners, E-commerce, Inkjet printers, Laser printers, Photocopiers, Typewriters...
Science
Science: Atoms, Bullets, Candles, Center of gravity, Centrifuges, Chocolate, Electron microscopes, Endoscopes, Energy, Forensic science, Fresnel lenses, Fuel cells, Happiness, Heat, Heat exchangers, Holograms, Lasers, Laser diodes, Laser eye surgery, Lenses, Light, Luminescence, Magnetism, Magnetrons, Microscopes, Mirrors, Linear motors, Nanotechnology, Newton's laws of motion, Sound, Soundproofing, States of matter, Superconductors...
Space
Space: Satellites, Space rockets, Space Shuttle, Space telescopes...
Tools
Tools: Autoclaves, Binoculars, Fire blankets, Fire fighting, Fire extinguishers, Fire hydrants, Fire sprinklers, Gas springs, Jackhammers/pneumatic drills, Night vision goggles, Pulleys, Robots, Tools and machines, Welding and soldering...
Transport
Transportation: Airbags, Airplanes, Bicycles, Bicycle helmets, Brakes, Car engines, Car history, Catalytic converters, Combine harvesters, Diesel engines, Driving efficiently, Electric bicycles, Electric cars, Elevators, Helicopters, Hovercraft, Hydrofoils, Jet engines, Outboard motors, Regenerative brakes, Steam engines, Submarines, Subway stations, V/STOL aircraft, Wheels and axles, Wind tunnels...
Buyer's guidesl
Buyer's guides: Computers, Digital cameras, Headphones, Web hosting...
Miscellaneous
Miscellaneous: Burgundy tourism, DIY advertising, History of happiness, How to pass exams, How to write a brilliant essay, Science and technology photo library, Orson Welles and obesity, Suicide in young people, Winston Churchill and alcohol...
Complete guides
Complete Guides: Careers, Credit, Gardening, Home electrics, Financial Advice, Photography, Legal Advice, Home Design, Plumbing, Property, Retirement, Start a Business, Woodworking.
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