Asynchronous

A method of data transmission in which one machine sends data, one character at a time, to another machine at variable intervals that do not need to be synchronized to a timing device, such as a system clock.

AUTOEXEC.BAT file

The batch file your computer runs automatically whenever you load MS-DOS. It configures the installed system devices and sets various user preferences. See also Batchfile.

Backup

An extra copy of a program, data file, or disk, that is created in case your working copy is damaged or lost.

Base memory

See Conventional memory.

Butch file

A type of file that executes a series of commands automatically. Batch files are text files with the filename extension .BAT. When you type the filename, your operating system executes all the commands in that file sequentially.

BIOS

Basic Input/Output System. Routines in ROM (Read Only Memory) that handle the transfer of information among various hardware components, and between the hardware and your operating system and other software.

2 Glossary