Computer viruses: nasty manmade software, usually aimed at IBM-compatibles. Virus programs are made in such a way that they latch onto one machine and then try to copy themselves onto other machines, either through floppy disks or through on-line connections. The worst of these programs can destroy all the data on a computer.
CPU (central processing unit): the metal or plastic computer ''box'' that holds the chips and central circuitry that makes the computer work.
Operating system: the software that controls the operation of the computer. The most popular flavor is Windows for IBM-compatible PCs, followed by the Mac's System 7.5.
Point-and-click: actions you perform with a computer mouse to make the computer do something.
Word-processing software: programs that let you type, edit, arrange, rearrange, and print out text-based documents.