Graphics
Information in the form of pictures or images. Also, the display of pictures or images on a computer’s display screen.
Guard Band
Narrow frequency band left unused between adjacent channels to minimize interference.
H
Half Duplex
Data transmission in which data may flow in either direction at one time, but not both directions simultaneously. Transmission direction is alternatively switched to allow two way flow of data.
Handshake
A predetermined interchange of signals between two devices to establish conditions for a transfer of data.
Hardware
The electronic or
Hardware Handshaking
The use of special
Harmonics
Frequencies which are integer multiples of some fundamental frequency.
Harmonic Distortion
A line impairment caused by equipment which distorts the original signal at multiples of the same fundamental frequency.
Hexadecimal Numbers
A number system with a base of 16. The first ten digits are represented by 0- 9 while the last six digits are represented by
HDLC
High Level Data Link Control. Communications protocol developed by the International Standards Organization.
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