Glossary Terms
Terms that are used on the Manufacturing Automation website
Hand shaking
contact among or between CPUs for identification.
Handshake
An interface procedure that is based on status/data signals that assure
orderly data transfer as opposed to asynchronous exchange.
Hardware
the physical, manufactured components of a computer system, such as the circuit boards, CRT, keyboard, and chassis.
Harmonic distortion
Continuous distortion of the normal sine wave, occurring at frequencies between 60 Hz and 3 kHz.
Heuristic
Describes an approach based on common sense rules and trial and error, rather than on comprehensive theory.
High-level language
A problem-oriented programming language in which each instruction may be equivalent to several machine-code instructions.
HMI
Human-machine interface
Host
1) A central controlling computer in a network system.
2) Any device on
a network system that provides a controlling function to another device
on the network.
3) Any intelligent device for which another device is
providing a communication interface to a network.
Host computer
the primary computer in a multi-processor network that issues commands,
accesses the most important data, and is the most versatile processing
element in the system.
Hot swap
exchange of components during operation.
HTML
Hyper text markup language
Hypertext
An interactive on-line documentation technique that allows users to
select ?? typically via a mouse click ?? certain words or
phrases to immediately link to information related to the selected item.
Hysteresis
1) The effect of residual magnetism whereby the magnetization of a
ferrous substance lags the magnetizing force because of molecular
friction. 2) The property of magnetic material that causes the magnetic
induction for a given magnetizing force to depend upon the previous
conditions of magnetization. 3) A form of nonlinearity in which the
response of a circuit to a particular set of input conditions depends
not only on the instantaneous values of those conditions, but also on
the immediate past of the input and output signals.
