A-Z index
Last updated: January 10, 2013.
How does it work? What makes it go? What's the science behind it? If those are the kinds of questions you like to ask, you've come to the right place! Explore our site and you'll find around 450 free, easy-to-understand articles (including around 2000 photos and 550 full-color, how-it-works illustrations), covering science, technology, gadgets, inventions, and how things work.
A word of explanation...
Our articles are designed for readers of all ages and abilities, though they're best for ages 10+ (10 through to adults). Some are much harder to understand than others. The stars in the list below give you a rough idea of how easy or hard each article is:
* A short, simple introduction, particularly suitable for young readers.
** A longer and more detailed article, suitable for most readers.
*** A more academic or technical piece. Young readers may find these articles too detailed and complex.
Obviously this is a very rough system. Don't let it put you off reading anything!
Most read
Our top-ten, most popular articles:
- Water pollution **
- Electric motors **
- Refrigerators *
- Electricity *
- Climate change and global warming **
- Air pollution *
- Heat insulation **
- Nanotechnology *
- Carbon monoxide detectors **
- Atoms *
Topics
Our articles are also arranged into these broad topic areas:
- Communications
- Computers
- Electricity and electronics
- Energy
- Engineering
- Environment
- Gadgets
- Home life
- Materials
- Science
- Tools, instruments, and measurement
- Transportation
A-Z list of articles
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
A
- AC induction motors **
- Accelerometers **
- Acidity (pH) meters **
- Activities, science fair *
- Adhesives (glues) **
- Advertising, do-it-yourself **
- Aerosol cans *
- Aerials (antennas and transmitters) *
- Aerodynamics **
- Airbags *
- Air conditioners *
- Airplanes *
- Airplane jet engines *
- Air pollution:
- Air purifiers, photocatalytic **
- Alarms:
- Alcoholism and Winston Churchill **
- Alloys **
- Alloys, shape-memory **
- Altimeters **
- Aluminum **
- Amplifiers *
- Ammeters **
- Analog versus digital technology *
- Analog radio **
- Anemometers (wind-speed meters) **
- Antennas and transmitters *
- Anti-reflective coatings (thin-film interference) **
- Anti-static coatings **
- Anti-theft security ink *
- Arc lamps (includes xenon lamps) **
- Artworks, how to draw scientific art *
- Atoms:
- Artificial limbs (prosthetics) *
- Augmented reality **
- Autoclaves *
- Automobiles, history of *
- Axles and wheels *
- Aztec codes (2D barcodes, data-matrix codes) **
B
- Baby-monitors (intercoms) *
- Balances and weights *
- Balloons, hot-air *
- Barcodes and barcode scanners **
- Barcodes, 2D (data-matrix codes) **
- Barometers (pressure measuring instruments) *
- Batteries:
- Beepers (radio pagers) **
- Bicycles:
- Bicycles (general introduction) **
- Bicycle helmets *
- Electric bicycles **
- Binoculars and field glasses **
- Biofuels **
- Biomass boilers *
- Biomimetic clothing *
- Bioplastics and biodegradable plastics **
- BitTorrent **
- Blister plasters **
- Blood-pressure monitors *
- Bluetooth **
- Blu-ray discs *
- Boats and ships *
- Boilers, biomass *
- Boilers, gas central heating *
- Books, electronic *
- Books, science reading list *
- Brain and Internet **
- Brakes:
- Breadmaking machines **
- Bricks *
- Bridges *
- Broadband Internet:
- Buildings **
- Bulletproof glass *
- Bullets **
- Buoyancy and floatation (ships and boats) *
- Burglar alarms **
- Burners, CD and DVD **
C
- Calculators *
- Cameras:
- Campaigns: how to run an effective local campaign **
- Cams, web **
- Cams and cranks *
- Candles *
- Capacitors *
- Capacitors (supercapacitors) **
- Carbon allotropes (graphene) **
- Carbon capture and storage (CCS) **
- Carbon monoxide detectors **
- Carbon offsets **
- Cardiac arrest treatment (defibrillators) *
- Careers in science and technology *
- Carburetors *
- Cars:
- Axles and wheels *
- Brakes *
- Carburetors *
- Electric and hybrid cars *
- Engines **
- Gears *
- History of cars *
- Catalysts, zeolite **
- Catalytic converters *
- CCDs (charge-coupled devices) *
- CDs (compact discs):
- Cellphones (Mobile phones) **
- Cellphone broadband (how HSDPA works) **
- Center of gravity *
- Central heating and gas boilers *
- Centrifuges *
- Ceramics **
- Cermets **
- Chainsaws *
- Charge-coupled devices (CCDs) *
- Chargers, induction **
- Chocolate science **
- CHP cogeneration **
- Chromatography **
- Chromic (color-changing) materials:
- Chromium **
- Churchill, Winston **
- Circuit breakers, RCD **
- Circuits, integrated **
- Clean coal and CCS **
- Cleaning cloths, microfiber *
- Climate change and global warming **
- Clocks:
- Clothes:
- Cloud computing **
- Cloudfront hotlinks, blocking ***
- Coffee (introduction and overview) *
- Coffee (pod) makers **
- Cogeneration **
- Color-changing (thermochromic) materials **
- Combine harvesters *
- Combined heat and power (CHP) **
- Compasses *
- Composites (composite materials) and laminates **
- Composting toilets **
- Compressors and pumps **
- Computers:
- Introduction *
- Beginner's guide *
- Buyer's guide **
- Cloud computing **
- Computer-aided design (CAD) *
- Computer models **
- Computer graphics **
- History of computers **
- Keyboards *
- Laptop repairs **
- Memory (general, RAM, ROM, etc) *
- Memory (flash memory) **
- Mice **
- Networks **
- Printers **
- Quantum computing **
- Computer screens, touch-sensitive *
- Speech synthesis **
- Supercomputers **
- Webcams **
- Concrete, reinforced **
- Conservation of energy, law of **
- Contact details for this website
- Converters, catalytic *
- Cookers:
- Copiers (photocopiers) **
- Copper **
- Cranks and cams *
- Criminal investigation *
- Cryptography **
- Cycles **
- Cycle helmets *
D
- d3o and energy-absorbing plastics **
- Data-matrix codes **
- Deafness, hearing aids for *
- Decibel sound level meters **
- Defibrillators *
- Dehumidifiers *
- Design, computer-aided (CAD) *
- Detectors, smoke **
- Detective work and criminal investigation *
- Detergents and soaps *
- Dictation (speech recognition) software **
- Diesel engines *
- Digital technology (general introduction) *
- Digital cameras:
- Digital pens **
- Digital radio **
- Diodes and light-emitting diodes (LEDs) **
- Diodes, laser **
- Directional loudspeakers **
- Dishwashers *
- Displays:
- Diving, scuba *
- DLP® television projectors **
- Doorbells, electric *
- Dots, quantum **
- Drilling *
- Drawing scientific artworks *
- Dryers, clothes (tumble dryers) **
- Dry-stone walls **
- DVDs and CDs *
- Dynamometers **
E
- Earbud headphones *
- Earthquakes **
- E-books (electronic books) *
- Eco-homes *
- Eco-labelling **
- Eddy-current brakes **
- Efficiency, driving **
- e-commerce **
- Electricity:
- Introduction *
- Electrical energy monitors *
- Electric cars *
- Electric bikes **
- Electric doorbells *
- Electric hub motors **
- Electric kettles **
- Electric motors **
- Electric motors, AC induction **
- Electric stepper motors **
- Electric showers *
- Electric toasters **
- Electric toothbrushes *
- Electric guitars *
- Electricity generators **
- Electricity transformers **
- Electric surge protectors **
- Fuses **
- Piezoelectricity **
- Static electricity *
- Triboelectricity *
- Voltage optimisation **
- Electrochromic smart windows **
- Electrolysis **
- Electrolyzers **
- Electromagnetic brakes (eddy-current brakes) **
- Electromagnetic spectrum *
- Electronic books (E-books) *
- Electronic ink and paper *
- Electronics:
- Electron microscopes **
- Electroplating *
- Electrostatic smoke precipitators *
- Elevators (lifts) *
- Encryption **
- Endoscopes *
- Energy:
- Energy-absorbing plastics **
- Engines:
- Environment:
- Environmentalism (introduction) **
- Air pollution (introduction and overview) **
- Air pollution (student research resources) *
- Climate change and global warming **
- Eco-homes *
- Land pollution **
- Organic food and farming **
- Public attitudes to the environment ***
- Recycling *
- Renewable energy *
- Water pollution **
- Essays, how to write them *
- Ethernet (computer networks) **
- Exams, how to pass **
- Experiments, examples of great physics **
- External combustion steam engines **
- External combustion Stirling engines **
- External sound cards **
- Eyeglasses, photochromic **
- Eye surgery, laser **
F
- Fair trade **
- Fax machines *
- Fiber optics *
- Field glasses and binoculars **
- Filament (incandescent) lamps *
- Film cameras and basic photography **
- Filters, HEPA *
- Fingerprint scanners **
- Fire:
- Candle flames *
- Fire blankets *
- Fire extinguishers *
- Fire fighting *
- Fire hydrants *
- Fire sprinklers *
- Fire-retardant fabrics (Nomex®) **
- Smoke detectors **
- Fireworks *
- Fission, nuclear *
- Flames, candles *
- Flares *
- Flash memory **
- Flatscreen television **
- Flight (airplanes) *
- Fluid dynamics (aerodynamics) **
- Flywheels **
- Fountain pens *
- Flush toilets *
- Flywheels (regenerative brakes) *
- Foam mattresses **
- Forensic science *
- Fountain pens *
- Fresnel lenses *
- Fridges (refrigerators) **
- Fuel cells **
- Fuel efficiency **
- Fuels, biofuels **
- Fuses and surge protectors **
- Fusion, nuclear **
G
- Galvanometers **
- Gas central heating boilers *
- Gases, liquids, and solids *
- Gas, liquified petroleum (LPG) *
- Gasoline engines **
- Gas plasma waste treatment **
- Gas springs **
- Gauges, strain **
- Gears *
- Geiger counters *
- Geoengineering **
- Generators, electricity **
- Glass:
- Global warming and climate change:
- Glues (adhesives) **
- Goggles, night vision *
- Gold *
- GORE-TEX® waterproof clothing **
- GPS satellite navigation *
- Gramophone *
- Graphene **
- Graphics, computer **
- Gravity, center of *
- Green eco-homes *
- Greywater **
- Green energy (renewable energy) *
- Griffin iMic external sound cards **
- Guitars, electric *
H
- Hall-effect sensors **
- Halogen cooking hobs **
- Handwriting recognition (OCR) **
- Happiness:
- Hard drives **
- Harvesters, combine *
- HDTV (high-definition television) **
- Headphones:
- Hearing aids *
- Hearing-impaired people, telephones for **
- Heat:
- Helicopters **
- Helmets, bicycle *
- HEPA filters *
- History:
- Home automation and smart homes **
- Home insulation **
- Holograms *
- Hosting web, buyer's guide**
- Hot-air balloons *
- Hot-water systems, solar **
- Hotlinks to Cloudfront, blocking ***
- Hovercraft and hydrofoils *
- HSDPA and mobile (cellphone) broadband Internet **
- Hub motors **
- Humidity meters (hygrometers) *
- HVAC air conditioners *
- Hybrid and electric cars *
- Hybrid solar lighting (HSL) *
- Hydrants, fire *
- Hydraulics **
- Hydrocolloidal plasters and wound dressings **
- Hydrofoils (covered under Hovercraft) *
- Hydrogen electrolyzers **
- Hydrogen fuel cells **
- Hydroponics **
- Hygrometers *
I
- Incandescent (filament) lamps *
- Induction chargers **
- Induction motors (AC) **
- Induction motors, linear **
- Induction cooktops **
- Infrared remote control **
- Injection lasers (semiconductor laser diodes) **
- Ink, electronic *
- Ink, invisible *
- Inkjet printers **
- Insulation, heat **
- Integrated circuits **
- Intercoms *
- Interference, thin-film **
- Interferometers **
- Internet:
- Intruder alarms **
- Inventors and inventions **
- Inverters **
- Invisible ink *
- Ionization smoke detectors **
- IPTV (Internet Protocol Television) **
- Iris scanners **
- Iron and steel **
J
- Jackhammers/pneumatic drills **
- Jet engines (airplane engines) *
- Jet Ski® and Sea-Doo® *
- Jobs in science and technology *
K
L
- Labels, eco **
- Laminates and composites *
- Lamps:
- Lamson (pneumatic transport) tubes *
- Laptop repairs **
- Lasers:
- Laws of motion *
- Lead *
- LCD (liquid-crystal display) screens **
- LEDs (light-emitting diodes) **
- LEDs, organic (OLEDs) and LEPs (light-emitting polymers) **
- Lenses:
- Lenticular printing *
- LEPs (light-emitting polymers) **
- Leucodyes (thermochromic materials) **
- Lie detectors (Polygraphs) *
- Lifts *
- Light *
- Light-emitting diodes (LEDs) **
- Lights:
- Limbs, prosthetic *
- Linear motors (induction motors) **
- Linux (computer operating system) **
- Liquids, solids, and gases *
- Liquid-crystal displays (LCD televisions) **
- Liquid crystals, thermochromic uses **
- Lithium-ion batteries **
- Local campaigns, how to run **
- Locks **
- Locomotives, steam **
- Logic gates **
- Loudspeakers **
- Loudspeakers, directional/parametric **
- Low-e, heat-reflecting windows**
- LP records and cassette tapes: converting to MP3 files **
- LP record players *
- LPG (liquified petroleum gas) *
- Lubricants *
- Luminescence *
M
- Machines, simple **
- Magnetic compasses *
- Magnetism *
- Magnetrons **
- Mass spectrometers **
- Materials science **
- Matter, states of *
- Mattresses, visco-elastic (memory-foam) **
- Media players (streaming media) **
- Memory, computer *
- Memory flash **
- Memory-foam mattresses **
- Metals:
- Metal detectors **
- Meters, moving-coil **
- Microfiber cleaning cloths *
- Microphones *
- Microscopes, optical *
- Microscopes, electron **
- Microwave ovens **
- Micro-wind turbines **
- Milk pasteurization *
- Mirrors **
- Misters and aerosol cans *
- Mobile broadband **
- Mobile phones **
- Models, computer **
- Modems *
- Molecular beam epitaxy **
- Molecular manufacturing (nanotechnology) **
- Motion *
- Motors:
- Mouse, computer **
- Moving-coil meters **
- MP3 players **
- Multi-factor authentication (security tokens) **
- Musical instruments:
- Electric guitars *
- Pianos **
- Synthesizers **
N
- Nanotechnology **
- Navigation:
- Neon lamps *
- Neoprene wetsuits **
- Networks, computer **
- Neural networks **
- Newton's laws of motion *
- Nickel **
- Night vision goggles *
- Nixie tubes **
- Noise-cancelling headphones **
- Noise-reduction (soundproofing) **
- Nomex® **
- Nonnewtonian materials (energy-absorbing plastics) **
- Nonstick cooking pans(Teflon® and PTFE) *
- Nuclear power:
- How nuclear power plants work (nuclear fission) *
- Nuclear fusion **
- Nylon *
O
- OCR (optical character recognition) **
- Ocean energy (OTEC) **
- Ohmmeters **
- Office photocopiers **
- OLPC: One laptop per child *
- One-time passwords (security tokens) **
- Optical character recognition (OCR) **
- Optical fibers *
- Optical scanners *
- Optical smoke detectors **
- Optics, thin-film **
- Organic food and farming **
- Organic LEDs and LEPs (light-emitting polymers) **
- Orson Welles and obesity **
- Oscilloscopes **
- OTEC (ocean thermal energy conversion) **
- Outboard motors *
P
- Padlocks *
- Paint *
- Pagers **
- Paper and papermaking *
- Paper, electronic *
- Parachutes *
- Parametric loudspeakers **
- Passive-solar energy **
- Passwords, one-time **
- Pasteurization *
- Pedometers *
- Pendulum clocks *
- Pens, digital **
- Pens, fountain *
- Personal Water Craft (PWC)—JetSki® and Sea-Doo® *
- pH meters **
- Phones (Cellphones/cellular phones/mobile phones) **
- Phones (landlines) **
- Phonograph *
- Phosphorescence *
- Photocatalytic air purifiers **
- Photocatalytic self-cleaning windows **
- Photochromic lenses **
- Photocopiers **
- Photoelectric cells **
- Photography:
- Photovoltaic (PV) cells **
- Physics experiments, examples of great **
- Pianos **
- Piezoelectricity **
- Planes (how they fly) *
- Plasma arc recycling **
- Plasma flatscreen televisions *
- Plasters, hydrocolloidal **
- Plastics:
- Platinum **
- Pneumatic drills/jackhammers **
- Pneumatic transport tubes *
- Pocket calculators *
- Pod coffee makers **
- Point-of-sale scanners, barcode **
- Pollution:
- Polygraphs ("lie detectors") *
- Power plants (power stations) *
- Power plants, CHP cogeneration **
- Power, solar electric **
- Power, solar thermal **
- Pressure cookers *
- Pressure washers *
- Printers and printing:
- Privacy policy **
- Probes, Hall-effect **
- Projection television **
- Propellers **
- Prosthetic limbs *
- Protective materials **
- Pulleys *
- Pumps and compressors **
- Pyranometers *
- Pyrometers **
- Psychology:
Q
- QR Codes® (2D barcodes, data-matrix codes) **
- Quantum computing **
- Quantum dots **
- Quartz clocks and watches *
R
- Radar **
- Radiation detectors (Geiger counters) *
- Radiation, electromagnetic (electromagnetic spectrum) *
- Radio:
- RCD circuit breakers **
- Reality, augmented **
- Reality, virtual **
- Rechargeable batteries **
- Record players *
- Recycling *
- Recycling, plasma arc **
- Reed switches *
- Refrigerators **
- Regenerative brakes *
- Relays **
- Remote control **
- Renewable energy *
- Repairing a laptop computer **
- Residual-current device (RCD) circuit breakers **
- Replacement (prosthetic) limbs *
- Resistors *
- RFID tags **
- Rivers *
- Robots:
- Rockets (space) *
- Rollercoasters *
- Roomba robot vacuum cleaners *
- RSS *
- Rubber **
S
- Sampling (Analog and digital technology) *
- Satellite navigation, GPS *
- Satellites *
- Saving fuel and energy **
- Schlieren photography **
- Scanners:
- Science activities for children *
- Science of buildings **
- Science of chocolate **
- Science of happiness ***
- Scientific artworks (how to draw) *
- Scuba diving *
- Sea-Doo® and Jet Ski® *
- Seas, extracting thermal energy from (OTEC) **
- Security tokens **
- Seismometers and seismographs (covered under Earthquakes) **
- Self-cleaning windows **
- Self-healing materials **
- Semiconductors (integrated circuits) **
- Semiconductor laser diodes **
- Sensors, Hall-effect **
- Shape-memory alloys **
- Shear-thickening, energy-absorbing plastics **
- Ships and boats *
- Showers, electric *
- Silver **
- Simple machines **
- Simulations, computer **
- Silicon-controlled rectifiers (thyristors) **
- Smart homes **
- Smoke detectors **
- Smoke scrubbers, electrostatic *
- Snowmobiles (includes snowmachines and Ski-Doos) *
- Soaps and detergents *
- Soil erosion and land pollution **
- Solar energy:
- Soldering and welding *
- Solids, liquids, and gases *
- Sound:
- Space rockets *
- Space telescopes **
- Spam—how to block it **
- Spectrometers, mass **
- Speech recognition software **
- Speech synthesis **
- Speedometers **
- Sphygmomanometers (blood-pressure meters/monitors) *
- Split-testing websites**
- Sport, science of**
- Spread-spectrum frequency hopping (Bluetooth) **
- Springs *
- Springs, gas *
- States of matter *
- Static electricity *
- Static, anti-static-electricity coatings **
- Steam engines **
- Steam turbines **
- Steel and concrete (reinforced concrete) **
- Steel and iron **
- Step counters (pedometers) *
- Stepper (stepping) motors **
- Sterilizing with autoclaves *
- Stirling engines **
- Stone (dry-stone) walls **
- Strain gauges **
- Streaming media **
- Strobe lights **
- Submarines **
- Suicide in young people **
- Sunglasses, photochromic **
- Sunscreen *
- Supercapacitors **
- Supercomputers **
- Superconductors **
- Surfing *
- Surge protectors **
- Surgery, laser eye **
- Swimming, science of *
- Switches, reed *
- Synthesizers, music **
- Synthesizers, speech **
T
- Talking computers (speech synthesizers) **
- Tapes, magnetic, and LP records: converting to MP3 files **
- Teaching guide: Ideas for using this website for curriculum-based science teaching **
- Teflon® and PTFE nonstick cooking pans*
- Telephones **
- Telephones for hearing-impaired people **
- Telescopes in space **
- Television:
- Television (general principles and cathode-ray tube TVs) **
- Television (3D) **
- DLP® television projectors **
- Internet Protocol Television (IPTV) **
- LCD televisions**
- HDTV (high-definition television) **
- Plasma televisions *
- Projection televisions **
- Text to speech (speech synthesis) **
- Thermal insulation **
- Thermochromic materials **
- Thermocouples **
- Thermometers *
- Thermometers, infrared (pyrometers) **
- Thermostats **
- Thermos® flasks *
- Thin-film deposition, molecular beam epitaxy **
- Thin-film interference **
- Three-dimensional (3D) printers *
- Three-dimensional (3D) television **
- Thyristors **
- Tin *
- Titanium **
- Toasters **
- Toilets:
- Flush *
- Composting **
- Tokens, security **
- Tools and machines **
- Toothbrushes, electric *
- Touchscreens *
- Tractors *
- Transformers (electricity) **
- Transistors **
- Transmitters and antennas *
- Trash recycling *
- Triboelectric effect (static electricity) *
- TTS (Text to speech/speech synthesis) **
- Tumble dryers (clothes dryers) **
- Tungsten **
- Tunnels *
- Turbines
- Turbochargers *
- TV remote control **
- Typewriters **
U
- Ultrasound *
- USB *
V
- Vacuum cleaners *
- Vacuum cleaners, Roomba robot *
- Vacuum flasks *
- Vacuum fluorescent displays (VFDs) **
- Valves *
- Vehicles, electric *
- Virtual reality **
- Visco-elastic, memory-foam mattresses **
- Vision, night *
- Voice Over Internet protocol (VOIP) **
- Voice recognition software **
- VOIP **
- Voltage optimisation **
- Voltmeters **
- Vertical/Short Takeoff and Landing (VSTOL) aircraft *
W
- Walkie-talkies *
- Walls:
- Washing machines:
- Waste recycling *
- Waste treatment, gas plasma **
- Watches and clocks (quartz) *
- Watches and clocks, radio-controlled *
- Water *
- Waterproof GORE-TEX® clothing **
- Water pollution **
- Water filters **
- Weather stations *
- Webcams **
- Websites:
- Weights and balances *
- Welding and soldering *
- Wetsuits **
- Wind-speed meters (anemometers) **
- Wheels and axles *
- Wheels, energy-storing (flywheels) **
- Wind tunnels *
- Wind turbines *
- Wind turbines (micro)**
- Windows:
- Windup (clockwork) mechanisms *
- Winston Churchill **
- Wireless Internet **
- Wireless remote control **
- Wood **
- Wood-burning stoves (biomass boilers) *
- World Wide Web (WWW) **
- Wound dressings, hydrocolloidal **
X
Y
- Yale locks *
- Yo-yos *