Glossary 1
Glossary

A

AC
(Alternating Current) The type of current available in wall outlets. All computers must
convert alternating current to direct current to operate. See also DC.
address
A label, name, or number that identifies a location in computer memory.
ASCII
(American Standard Code for Information Interchange) A standard number assigned to each
of the alphanumeric characters and keyboard control code keys to enable the transfer of
information between different types of computers and peripherals.

B

backplane slot
A connector on the backplane board in desktop computers and expansion boxes that allows
you to install circuit cards.
backup
A copy of data for safe-keeping. The data is copied from computer memory or disk to a
floppy disk, magnetic tape, or other media.
backup battery
The battery in your computer that maintains the real-time clock and the configuration
information when the computer's power is removed.
base memory
An area of memory between 0 and 640 kilobytes.
baud rate
The speed with which data is transmitted during serial communication. The computer's
operating system and software program must be configured for the same baud rate as the
communication device, such as a serial printer. See also bps.
BIOS
(Basic Input/Output System) A program stored in flash EPROM or ROM that controls the
keyboard, disk drives, video monitor, and other devices. See also flash EPROM, EPROM,
and ROM.
bit
Derived from BInary digiT, a bit is the smallest unit of information a computer handles. See
also byte.