Computers and peripherals. Two personal computers, and peripherals on an office desk. The computers (middle left and middle right) each consist of a monitor (screen), processor unit, and keyboard. Between the computers lie a stack of computer peripherals; from top to bottom: a modem, a disc drive and a Compact Disc-Read Only Memory (CD-ROM) device. The monitor relays data to the user. The processor does calculations and stores the computer's memory. The keyboard is used to enter commands. A modem links one computer to another through a telephone line. A disc drive retrieves data from, and writes it to, floppy discs. A CD- ROM can only read data from a compact disc.