Computers.

5. A segment of self-replicating code planted illegally in a computer program, often to damage a system.
6. A computer input device for controlling the pointer on a display screen by sliding the finger along a touch-sensitive surface.
9. A video camera that feeds its images in real time to a computer network.
12. A device for projecting a beam of light.
13. An output device that produces a paper copy of alphanumeric or graphic data.
16. Senses the user pressing directly on the display.
18. A combination of two or more cells electrically connected to work together to produce electric energy.
19. A global system of interconnected computer networks.
20. A portable, usually battery-powered microcomputer.

1. A set of keys used to input information to a computer.
2. A palm-sized, button-operated pointing device.
3. The components of the computer in which such information is stored.
4. An electromechanical device which produces sound.
7. A pair of small loudspeakers which are designed to be held in place close to a user's ears.
8. A thin, flexible plastic disk coated with magnetic material, on which data can be stored for later use.
10. An acoustic sensor that provides input by converting sound into electrical signals.
11. A lever used to control movement of a cursor or other graphic element for video games.
14. Also called processor.
15. A pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball.
17. A component, as a CRT, with a screen for viewing data at a computer terminal.