Source diskette

The diskette that you are copying files from, as opposed to the target diskette, which is the diskette you are copying files to.

Stop bit

A signal sent in serial communications to mark the end of a character.

Subdirectory

A disk directory that branches down from another subdirectory or from the root directory.

Switch

An option added to an MS-DOS command that affects the way the command works. See Parameter.

System diagnostics

A set of programs you can run to verify the integrity of the computer’s hardware components. See Appendix D.

System diskette

A diskette from which the operating system can be booted. An MS-DOS system diskette must contain the file COMMAND.COM plus two hidden MS-DOS program files. To create a system diskette, use the /S switch with the FORMAT command (for example, FORMAT A: /S).

Target diskette

The diskette that you are copying files to, as opposed to the source diskette, which is the diskette you are copying files from.

TPI

Tracks Per Inch. A measure of the density with which data can be stored on a diskette.

Track

A circular region on a diskette, which is divided into sectors. Each side of a 1.44MB or 720KB diskette has 80 concentric tracks. Each side of a 360KB 5 1/4-inch diskette has 40. On a hard disk, tracks are called cylinders.

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