| Keyword | Definition |
|---|---|
| alphabet | a way of representing messages using written symbols to represent words and sounds |
| ASCII | a way of representing messages using a different number for each letter of the alphabet and used by computers to send the numbers as binary digits |
| braille | a way of representing messages using bumps on a surface that blind people can read using their fingers |
| hieroglyphics | a way of representing messages using pictures to represent words |
| morse code | a way of representing messages using sequences of dots and dashes often transmitted as beeps over radio waves |
| semaphore | a way of representing messages using sequences of flags to send signals by line of sight |
