Glossary
Default
A value, action or setting that is automatically used by a computer system when no other explicit information has been given.
Demodulate
To recover the information being transmitted by a modulated signal. For example, a conventional radio receiver demodulates an incoming broadcast signal top convert it into sound emitted by a speaker. See also Modulate and Modem.
Device
A piece of equipment connected to a computer — maybe a Fax Card or Modem.
Dial-up
Establishing a temporary connection to a remote system or computer via the public switched telephone network.
Dial Tone
A call progress signal returned by a telephone switching machine to indicate that it is ready to accept a telephone number.
Dibit
A grouping of two bits.
Digital Signal
A signal composed of discrete signal levels as opposed to the continuous signal levels of an analog signal.
Direct Keying
In videotex terminology direct keying refers to accessing a page by specifying its page number rather than using index pages.
Distortion
Undesired change in a signal’s original waveform resulting from the characteristics of the transmission circuits or other external influences.
Downloading
See Software Downloading.
DTE
An acronym of Data Terminal Equipment. See Data Terminal Equipment.
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