Manual

Glossary-6 User’s Manual
Glossary
DC: Direct Current. Electric current that flows in one direction. This type of
power is usually supplied by batteries.
default: The parameter value automatically selected by the system when
you or the program do not provide instructions. Also called a preset
value.
delete: To remove data from a disk or other data storage device.
Synonymous with erase.
device driver: A program that controls communication between a specific
peripheral device and the computer. The CONFIG.SYS file contains
device drivers that MS-DOS loads when you turn the computer on.
dialog box: A window that accepts user input to make system settings or
record other information.
disk drive: The device that randomly accesses information on a disk and
copies it to the computer’s memory. It also writes data from memory
to the disk. To accomplish these tasks, the unit physically rotates the
disk at high speed past a read-write head.
disk storage: Storing data on magnetic disk. Data is arranged on
concentric tracks much like a phonograph record.
diskette: A removable disk that stores magnetically encoded data used on
a microcomputer. Also called floppy disk.
diskette drive: An electromechanical device that reads and writes to
floppy disks. See also diskette.
display: A CRT, plasma screen, LCD, or other image producing device
used to view computer output.
documentation: The set of manual and/or other instructions written for the
users of a computer system or application. Computer system
documentation typically includes procedural and tutorial information
as well as system functions.
DOS: Disk operating system. See operating system.
driver: A software program, generally part of the operating system, that
controls a specific piece of hardware (frequently a peripheral device
such as a printer or mouse).
E
echo: To send back a reflection of the transmitted data to the sending
device. You can display the information on the screen, or output it to
the printer, or both. When a computer receives back data it
transmitted to a CRT (or other peripheral device) and then
retransmits the data to the printer, the printer is said to echo the
CRT.
EGA: Enhanced Graphics Adapter. A video display protocol defined by the
IBM Enhanced Graphics Adapter and its associated circuitry for
direct drive TTL displays that supports 16-colour/monochrome
640x350 and 16-colour 640x200 and 320x200 graphics, and
16-colour 640x350 and 320x350 text modes.