Asynchronous

A method of data transmission in which one device sends data one bit at a time to another device. This method allows for delays of any length between characters.

AUTOEXEC.BAT file

A special kind of batch file MS-DOS executes automatically each time you turn on or reset the computer.

Backlighting

The internal fluorescent illumination of the computer’s LCD screen. LCD screens that are not backlit are not legible without an external source of light.

Backlight period

The length of time your LCD screen stays illuminated in the absence of keyboard activity. To restore backlighting to your screen after the backlight period has elapsed, press any key. To change the backlight period, run the SETLCD program (see Chapter 2).

Backup

A copy of a program, data file, or disk, kept in case the original is damaged or lost.

Batch file

A text file containing one or more MS-DOS commands, each stored on a separate line. You use batch files to automate MS-DOS operations. When you type the name of the batch file (with or without its .BAT extension), each command in the file executes in sequence.

2 Glossary