mail-merge application: An application that takes names and addresses from a data base and puts them into form letters.

main circuit board: A large circuit board that holds RAM, ROM, the microprocessor, custom integrated circuits (chips), and other components that make the computer a computer.

main menu: The first menu you see in keyboard-based applications. It presents the application's top level of options.

mass storage device: A device, like a hard disk, that can store the equivalent of dozens of disks.

megabyte: A million bytes—a unit of measurement that comes in handy when you're describing the capacity of CD ROMs, which can store more than 550 megabytes.

megahertz: Abbreviated MHz One million cycles per second.

memory: Integrated circuits (chips) that store instructions for the microprocessor. There are two kinds of memory: temporary memory (called random-access memory—RAM) and permanent memory (called read-only memory—ROM) The contents of RAM disappear when you turn off the power; the contents of ROM do not.

memory expansion card: An interface card that you can connect to the memory expansion slot in the Apple IIGS to increase-the memory by 1 to 8 megabytes.

menu: A list of choices.

menu bar: In mouse-based applications, the horizontal strip at the top of the screen that contains menu titles.

menu title: A word, phrase, or picture in the menu bar in mouse-based programs that designates one menu. When you point to a menu title and hold down the mouse button, you can see what's on the menu.

MHz: See megahertz.

microprocessor: The brain of the computer—the processor of information. The Apple IIGS has a 65C816, 16-bit microprocessor.

MIDI: Stands for Musical Instrument Digital Interface. A software and hardware standard set by the music industry that allows different electronic instruments to communicate with each other and with computers.

MIDI card: An interface card that lets you use your Apple IIGS as a music synthesizer or as a control device for electronic musical instruments

mode: A state that determines the computer's behavior.

modem: Short for modulator/demodulator. A device that links your computer to another computer or an information service over phone lines.

Modula-2: A programming language.

monitor: Like a television set without channels. It displays instructions from the application to you and shows what you've typed into memory.

monochrome monitor: A black-and-white, amber-and-black, or green-and-black monitor.

mouse: The small device you roll around on a flat surface next to your computer. When you move the mouse, the pointer on the screen moves correspondingly.

mouse-based application: An application that accepts input from a mouse.

Glossary

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