Communications

• Analog versus digital technology: What are the differences between analog and digital? Which is better?
• Antennas and transmitters: How do we send and receive radio waves from one place to another?
• Bluetooth: A simple way to connect wirelessly to nearby electronic equipment.
• Digital cameras: How a digital camera represents photographs in numeric form.
• Film cameras and photography: Old-style photography uses light-sensitive film to capture images of the world.
• Cellphones (Mobile phones): How mobile telephones use radio waves to field calls.
• Data-matrix codes: Two-dimensional barcodes that store much more information.
• Directional loudspeakers: Loudspeakers that focus sound on a very specific area.
• Electronic ink: Why is the display of an electronic book easier to read than a computer screen?
• Fax machines: How to send pictures down an old-style phone line.
• Fiber optics: How light can zoom down glass and plastic cables, taking computer data with it.
• Flares: Guns that send warning signals high into the air.
• Fountain pens: Why pens need to fill up with air to make ink flow onto the page.
• History of communication technology: How did we get from the alphabet to the Internet?
• Internet: The world's most important communications network.
• Headphones: Loudspeakers that clamp onto your ears. We take them apart and look inside!
• Headphones (repairing): Earbuds break easily. Here's how to fix them yourself!
• Lenticular printing: How can you make a book cover change its appearance as you tilt it from side to side?
• LIDAR: How can you navigate or map the world with a scanning laser beam?
• Loudspeakers: How to turn electricity and magnetism into Bob Dylan or Beethoven!
• LP record players: Before we had iPods and CD players, music came on thin plastic circles.
• Microphones: The opposite of loudspeakers, they turn sound into electrical signals.
• Pagers: Radio waves can be used to catch your attention if you're carrying a pager.
• Photocopiers: How a bright light and static electricity can make a copy of a printed page.
• Printing: Classic printing technology explained, from ancient times to modern.
• Radar: Using radio waves to locate hidden objects.
• Radio: Electromagnetic waves travelling at the speed of light can carry information through the air.
• RFID tags: They're in your library books, on things you buy in shops, and maybe even in your pet!
• Satellites: Buzzing over our heads, they take photos, help us forecast the weather, and relay phone calls.
• Telephones: Old-style phones use microphones, loudspeakers, and wire connections stretched between them.
• Typewriters: Imagine writing your blog with gears, levers, and springs—that's how a typewriter puts your words on the page!
• Ultrasound: Using sound waves to see inside objects, from airplane engines to expectant mothers!
• Walkie-talkies: Short-wave radio is still a favorite way for police and the military to keep in touch.