Toshiba PORTEGE M400 User Manual
Page 243
User’s Manual
Glossary--6
Glossary
D
data: Information that is factual, measurable or statistical that a computer
can process, store, or retrieve.
data bits: A data communications parameter controlling the number of bits
(binary digits) used to make up a byte. If data bits = 7 the computer
can generate 128 unique characters. If data bits = 8 the computer
can generate 256 unique characters.
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.
display: A CRT, LCD, or other image producing device used to view
computer output.
documentation: The set of manuals 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).
DVD-R (+R, -R): A Digital Versatile Disc-Recordable disk can be written
once and read many times. The DVD-R drive uses a laser to read
data from the disc.
DVD-RAM: A Digital Versatile Disc-Random Access Memory is a high-
capacity, high performance disc that lets you store large volumes of
data. The DVD-ROM drive uses a laser to read data from the disc.
DVD-R DL: A disc having two layers on one side with the DVD-R storage
capacity about 1.8 times larger than before. The DVD-RW drive
uses a laser to read data from the disc.