music synthesizer: A device that can generate a variety of sounds, including those of traditional musical instruments.

MouseText: Special characters, like check marks and little apples, used in mouse-based applications.

MS-DOS: The operating system for applications designed to run on IBM and IBM-compatible personal computers.

music application: An application that can teach you how to read music or help you compose music.

music synthesizer: A device that can generate a variety of sounds, including those of traditional musical instruments.

network: A bunch of computers linked together so they can share information and peripheral devices.

NTSC composite color monitor: The standard video format defined by the NTSC, the National Television Standards Committee.

numeric keypad: The number keys, on the right side of the Apple IIGS keyboard, that are laid out like the keys on an adding machine. You can use them interchangeably with the number keys on the top row of the keyboard.

odd parity: An error-checking system in which the sending device adds an extra bit set to 0 or 1 as necessary to make the total of 1 bits add up to an odd number. The receiving device adds the 1 bits and if the total is an odd number, it assumes the message came through intact.

on-line: The condition of a device being connected or of data being accessible to the computer.

Open Apple: The Open Apple key that you can use to control the way other keys work in an application. Also called the Command key or represented with a propeller symbol.

open architecture: A computer that has an "open-lid policy"—it invites add-on devices.

operating system: An application that, among other things, controls the way information is loaded into memory, the way the computer works with the information, the way information is stored on a disk, and the way the computer communicates with a printer and other peripheral devices. ProDOS, DOS 3.3, and Pascal are three operating systems available for the Apple IIGS.

Option key: A key on the Apple IIGS keyboard that, when pressed in conjunction with another key, creates a special effect. On other models of the Apple II, this key is labeled Closed-Apple.

output: Information traveling out of the computer.

parallel device: A printer or other device that sends and receives data eight bits at a time over eight parallel wires. Compare serial device.

parallel interface: The condition of a computer and a peripheral device exchanging information eight bits at the same time along eight parallel wires. Compare serial interface.

parity: A way of checking data to make sure bits of data didn't get lost or garbled during transmission. See even parity and odd parity.

Pascal: A programming language taught in high school and college computer-science courses because it stresses a systematic approach to problem solving.

password: A secret word that gives you, but no one else, access to your data or to messages sent to you through an information service.

178

Glossary