Disk drive

The physical device that allows the computer to read from and write to a disk. A diskette drive has a disk slot into which you insert a diskette. A hard disk is permanently fixed inside the main unit.

Diskette

A flat piece of flexible plastic coated with magnetic material and used to store data permanently. Also called floppy disk.

DOS

The Disk Operating System that controls the computer’s input and output functions. See Operating system.

Double-density

A type of diskette format that allows you to store twice as much data as the standard-density format.

Extension

A suffix of up to three characters that can be added to a file name to better identify it.

File

A group of related pieces of information called records, or entries, stored together on disk. Text files consist of words and sentences. Program files consist of code and are used by computers to interpret and carry out instructions.

File name

A name of up to eight characters that MS-DOS uses to identify a file.

Floppy’ disk

See Diskette.

Format

To prepare a new disk (or erase an old one) so that it can store information. Formatting a disk divides it into tracks and sectors and creates addressable locations on it.

Graphics

Lines, angles, curves, and other nonalphanumeric data.

F-4

Glossary