Glossary
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double-click — To press and release the pointing device’s primary
button rapidly twice without moving the pointing device. In the
Windows
®
operating system, this refers to the pointing device’s left
button, unless otherwise stated.
double-density diskette — A 3.5-inch diskette that can hold up to
720 KB of information (half the capacity of a high-density diskette).
See also diskette, high-density diskette.
download — (1) In communications, to receive a file from another
computer through a modem or network. (2) To send font data from
the computer to a printer. See also upload.
drag — To hold down the mouse button while moving the cursor to drag
a selected object. In the Windows
®
operating system, this refers to
the left mouse button, unless otherwise stated.
driver — See device driver.
DVD — An individual digital versatile (or video) disc. See also DVD-
ROM.
DVD-ROM (digital versatile [or video] disc read-only memory) — A
very high-capacity storage medium that uses laser optics for reading
data. Each DVD-ROM can hold as much data as several CD-ROMs.
Compare CD-ROM.
E
emulation — A technique in which a device or program imitates another
device or program.
enable — To turn on a computer option. See also disable.
executable file — A computer program that is ready to run. Application
programs and batch files are examples of executable files. Names of
executable files usually end with a .bat or .exe extension.
expansion device — A device that connects to a computer to expand its
capabilities. Other names for an expansion device are port expander,
port replicator, docking station, or network adapter.
extension — See file extension.
external device — See device.