Glossary 149
disk drive—The device that reads and writes information and
applications on externa l media or hard disk. It rotates the disk at
high speed past one or more read/write heads.
document—Any file created with an application and, if saved to disk,
given a name by which it can be retrieved. See also file.
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.
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 pointer 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.
Eemulation—A technique in which a device or application imitates
another device or application.
enable—To turn on a computer option. See also disable.
eSATA—An external device that supports hot swapping and fast data
transfer. Very useful in storing and transferring large files.
executable file—A computer application 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.