| A | B |
|---|
| Modem | communicates with other computers over telephone lines. |
| Input | the first stage in the operation of a computer |
| Trackball | is used instead of a mouse on a laptop or notebook computer. |
| light pen | enables the user to write words or draw pictures directly into a computer |
| Keyboards | the main input device |
| scanner | a peripheral unit that uses light and devices that sense light to digitize photos and illustrations. Also reads bar codes at stores. |
| microphone | translates sound into electric current, which the computer digitizes |
| voice activator | uses a microphone and digitizer to help a computer recognize spoken words |
| touch screen | enables user to select options directly on the screen using pen based computers or a finger |
| Sholes/Qwerty | most common type of keyboard |
