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Electronics
-A glossary of terms.
Many
readers confronted with new language terminology in the
field of computer and electronics. As a basic guide we are
proud to present the most important part of this glossary
compiled in England.
A
Access:
To enter data in or retrieve it from memory storage.
Access
Time: The length of time required to store or
retrieve data, or to access a word in main memory. In other
words, the time passing, say, between giving a 'read' signal
and the data being available at the output.
Acoustic
Coupler: A device which converts data (in
digital form) into sequence of tones (analogue signals), so
enabling transmission over standard telephone lines. An
acoustic coupler is connected by inserting a standard
telephone hand set into two rubber cups that are attached
directly to the terminal from which data is being
transmitted, or to a separate modem. At the receiving end
the tones are converted back tot digital form by a modem.
Address:
A number of reference, which identifies a unique location in
a computer's memory.
ALGOL:
The contraction of Algorithmic language, a high level
programming language used for scientific computations.
Alphanumeric:
Data that consists of numbers and alphabetic characters.
Analogue:
The representation in electrical values of non-electric
physical quantities. For example, sound (pressure
variations) can be represented in analogue form by an
alternating voltage derived from microphone.
Analogue
Computer: One that performs its tasks, my
measuring continuous physical variables (perhaps volume,
voltage, pressure, length, flow), manipulating them to
obtain a solution and transforming the solutions into a
numerical equivalent.
Antiope:
The name of the broadcast teletext service of France.
Array:
A group of two or more logically related circuit elements,
gates for example, identified by a single name (gate array).
ASCII:
The acronym of American Standard Code for information
interchange, a standard code (of eight bits per character)
established by the American National Standards Institute to
achieve compatibility between various types of data
processing and communications equipment.
B
Bar
Code: A means of representing characters by a
series of lines and spaces of varying width which can be
read by an optical scanning device.
BASIC:
The acronym of Beginners all-purpose Symbolic Instruction
Code, a popular easy to learn programming language used in
many microcomputers. Despite its simplicity of use, it
contains many advanced features for handling alphanumeric
data and information.
Baud:
A unit of measurement (after baudot, a telegraph pioneer)
that denotes the rate of transmission of signal element per
second e.g. a device that transmits 300 bits per second can
be said to transmit at 300 baud.
BCD:
The acronym of Binary Coded Decimal, the representation of a
decimal number in binary code form. In the simplest BCD
code, four digits represent each figure.
Binary:
Literally of a pair of two parts. A system of communication,
particularly counting, using two possible states in coded
combinations.
Binary
Code: The representation of data by groups of
binary digits or, more generally, by any two symbols like
the dot and dash of Morse code.
Bit:
A contraction of Binary Digit, a digit in the binary number
represented by a 0 or a 1. It is the smallest unit of
storage in the computer. Groups of bits from other units of
storage, such as a byte or word.
Boot
(Strap): The term used to refer to the entering
of one or more instructions to initiate the execution of
permanently stored instructions which then load the
operating system or a computer.
Breadboard:
A board on which experimental electronics
circuits can be laid out.
Bubble
Memory: A type of solid state memory device,
which uses the magnetic properties of single crystals.
Bubble memory is capable of storing very large amounts of
data in a very small space. Access time is also very short.
Buffer:
An area of storage in a system, which is used temporarily to
hold data, being transferred from one device to another.
Bureaufax:
The term adopted by the Comite Consultatif International de
Telephonie et Telegraphie for the facimiline service
operating between postal/telecommunication authorities.
Bus:
A main highway in an electrical circuit.
Byte
(Bite): A number of bits which as a group
encodes a letters, number or part of a word in digital
notation.
C
CAD:
Computer Aided Design.
CAM:
Computer Aided Manufacture.
Capacitor:
A passive electronic component.
Captain:
The videotex/viewdata systems of Japan.
CAT:
Computer Aided Teaching.
Cathode:
in electron tubes, the electrode from which an emission of
electrons take place. In photocells and some camera tubes,
the electrode from which electrons are released when light
is present.
CBMS:
The acronym of Computer Based Message System. A term used in
the United States to cover the communication of information
by electronic mail systems.
Ceefax:
The BBC (British) broadcast teletext service.
Chip:
Microchip, microcircuit, and integrated circuit, IC). The
term for a small wafer of silicon or similar material on
which various circuit elements, such as transistors, diodes
and resistors, are produced. These circuit elements are
connected to form complete (thus 'integrated') electronic
circuits.
Closed
Lop (Systems): The type of system in which
there can be response to feedback from, say, a sensor or
control device, without intervention from an operator.
COBOL:
Contraction of Common Business Oriented Language, a computer
programming language particularly designed to express
business data proceessing problems in a recognizable
language.
CPU:
Central Processing Unit, the heart of the computer, which
incorporates the memory, control and airthmatic units.
Crash:
The term used to indicate that a computer system has stopped
working.
CRT:
Cathode Ray Tube. A vacuum tube enclosing an electron gun to
generate a beam of electrons, a system of focussing the beam
to produce a spot at the point of impact on the phosphor
screened, for the electric field deflection electrodes. A
television picture tube is perhaps the best known example of
a CRT.
Cursor:
The character or symbol displayed on a screen, which
indicates where the next character to be generated will
appear. It can be moved by various keys on a keyboard and
positioned to make alternations at that point.
D
Daisy
Wheel: A flat circular print element with two
characters on each of the spokes that radiate out from a
Center hub.
Database:
highly structured computer files that include a wide e range
of data and allows programmers or users to access only those
items they need.
Datacom:
A data communication service connecting major cities in the
United States, operated by Western Union.
DBS:
Direct Broadcasting by Satellite.
Debug:
to trace and correct errors in programming, code or hardware
malfunctions in a computer system.
Decoder:
A circuit used to interpret a specific code.
Dedicated:
Designating a resource that is reserved for a specific
programme, function or user.
Deflection:
In a cathode ray tube, electron beams are passed through an
electric or magnetic field, whereby the beam is deflected
from the path that would follow in the absence of such
fields. By the use of varying magnetic or electric
deflection fields, the beam traces a line of excitation on
the phosphor screen. By moving two fields, deflection can be
in two directions.
Degauss:
To erase data recorded in a magnetic tape.
Digital:
Referring to the binary representation of numerical
quantities by the number of discrete signals or the presence
or absence of them in particular positions.
Disk,
Disc, Diskette: An abbreviation for magnetic
disk. A storage device consisting of a circular disc with a
magnetisable coating on which data is stored on either or
both of its sides.
Disk
Drive: The unit that reads and writes data
stored on a disk.
DMA:
Direct Memory Access.
Dot
Matrix Printer: A printer that uses a matrix of
dots to make up the characters.
Dump:
To copy or transfer the contents of a computer file.
Duplex
(channel): A communication channel that allows
data to be transmitted in both directions simultaneously.
E
EDP:
Electronic Data Processing.
Electronic
Mail: The use of electronic methods to capture
transmits and delivers information.
Electron:
Negatively charged fundamental constituents of the atom.
Electron
Tube: An alternative term for the thermion
valve.
Electrostatic
Printer: A printer which produces characters by
means of wires or pins that supply an electrical charge in
the desired pattern to aluminum coated paper. Particles of
dry ink adhere to the magnetized areas and are then fixed by
heat.
Encoder:
A circuit, which puts information into a coded form. When a
key on a keyboard is pressed it activates a signal which
then has to be converted into the corresponding code for
that key.
Expert
system: These are programmers run on computers,
which attempt to store all the known information on a
particular subject usually obtained from the experts in that
field. In operation these system try to emulate an expert's
thought process in order to solve problems i.e. medical
diagnosis.
F
Facimiline
(Fax): The transmission over communication
lines of an image, in the form of electrical signals, to
another locations where they are reproduced as a copy of the
original.
Fail-safe:
Designating a system that continues to operate after a
malfunction occurs.
FEP:
Front-end Processor.
Fiber
Optics: The technology of transmitting data
over communication lines made from thin flexible strands of
glass or plastic through which laser or light beams can be
passed to transfer data.
File:
In computer programs, a collection of logically related
records dealt with as one unit.
File
protection: method by which a file is protected
(usually by means of passwords) from unauthorized use.
Flip-flop:
one of the most common circuit in a digital computer that
maintains a value of 1 or 0 units a trigger directs it to
change. It is thus a unit capable of storing a bit.
Floppy
disc: A flexible plastic disc coated with a
material that can be magnetized to store bits. Information
is written or read from them with the aid of floppy disc
drive.
Fortran:
Contraction of formula Translator, a computer programming
language used to write program dealing primarily with
mathematical formulas and expressions.
G
Gateway:
A link between different communications networks enabling
information to pass from one to another.
GIGO:
Garbage in - Garbage Out. The output of a computer is
determined by the input.
H
Hard
copy: Printed material in paper.
Hard
disk: A means of storing bits (information in
binary form) which takes the form of a disk mode of a rigid
base (ceramic, aluminum etc.), coated with a magnetic
material.
Hardware:
The actual physical equipment and components of a computer
system.
I
IC:
Integrated Circuit. A silicon chip containing numerous
interconnected electronic component transistors, diodes,
resistors, and capacitors.
Image
Intensifier: One that operates by striking
individual raised characters or wire ends against on inked
ribbon and paper.
Information
Technology: All the technologies, collectively,
that deal with the computer-assisted collection, processing
and transmission of information.
InfraRed:
Radiant energy, mainly heat, at wavelengths longer than
visible red.
In
- Line (processing): The processing of items in
the order in which they were input, without sorting, editing
or grouping.
Intelligent
(terminal): One that can perform certain
processing functions on data before it is transmitted to the
computer.
Interactive:
A two- way system that enables both the sending and
receiving of information.
Interface:
This means of interactions between two devices or systems
that handle data in different ways.
IP:
Information Provider. A term used to refer to those
providing information for teletext, viewdata and database
services.
I
/ O: Input Output.
ISO:
International Standards Organization, a voluntary
organization concerned with international standards for data
communication.
K
K:
Abbreviation for Kilo
Keyword:
A significant word in a title or text that describes the
content of text.
L
Laser:
Light Amplification by Stimulated Emission of Radiation, a
device that emits a very intense, narrow beam of light
formed of waves that have been amplified and concentrated.
LCD:
Liquid Crystal Display, where the crystals are sealed
between two pieces of glass and are activated by an external
light source. Used in calculators and digital watches.
LED:
Light Emitting Diode, a semiconductor device that emits
light when a current is passed through it.
Line
format: The number of lines used to compile a
TV picture. The present UK standard is 625.
M
Machine
(code or language): Each computer has its own
machine language and codes.
Memory:
As the name implies, the part of computer which stores
information in a retrievable form. The information may be
stored in variety of ways.
Menu:
A displayed list of the various functions, which can be
selected on a terminal.
Microcomputer:
A small computer.
Microprocessor:
The essential active working part of a microcomputer.
Minicomputer:
A computer of a size between a microcomputer and mainframe
model.
Modem:
Modulator-Demodulator, a device that converts signal from
one form to another and allows data to be transmitted over
telephone circuits. An acoustic coupler (q.v.) is a type of
a portable modem.
MPU:
MicroProcessor Unit.
Multiplexing:
The process of using a single device to handle
simultaneously several similar, but separate devices or
operations by altering its attention amongst them.
O
OCR:
Optical Character Recognition.
On-line:
To describe a terminal that is communicating with and
subject to the control of a central computer.
Oracle:
The British Independent TV Companies teletext service. In
addition to providing news and information it is used for
advertisements and subtitling some TV programs.
P
Pascal:
A computer programming language designed to support the
concepts of structured programming with each programming
following to precise form.
PCB:
Printed Circuit Board.
Peripheral
(unit): Equipment, such as printer, which adds
on to the computer.
Petal
Printer: Synonymous with daisy wheel printer.
Pixel
(or pel): A picture element on a display (e.g.
TV) Screen.
Printed
circuit: An electronic circuit formed by
applying conductive material in fine lines or other designs
to an insulating sheet, so reducing the need for wiring
connections.
Prestel:
The British Telecom public Videotex of view data service.
Printout:
The type-on-paper output from a computer.
Program:
The instructions, which determine the action of a computer.
Prompt:
A message that requests the operator to enter information.
Protocol:
A set of rules governing the communication and transfer of
data between two or more devices in communication system.
Q
Qwerty:
The standard typewriter keyboard.
R
RAM:
Random Access Memory, a re-writable memory in which any
location can be accessed directly without having to follow a
sequence of storage locations.
Redundancy:
The amount of that can be eliminated from an item of data
without losing the information to be conveyed.
Relay:
In circuits, an electronically operated switching device for
opening or closing a circuit path or changing circuit
characteristics.
ROM:
Read Only Memory, one which can not easily be overwritten
and is only accessible, by the user, i.e. where permanent
information is stored.
S
Semiconductor:
A material, which has an electrical conductivity between
that of an insulator and a good conductor like copper.
Silicon and germanium are typical semiconductors whose
conductivity are poor at low temperatures, but is improved
by minute additions of certain substances, or by the
application of light heat or voltage.
Software:
The programs, routines and documentation for computers and
data processing equipment.
Solid
state: Pertaining to semiconductor electronic
devices. Opposite to thermionic device.
T
Telefax:
The CCITT term used in Europe for public facimiline services
via public telephone networks.
Teleprinter:
A typewriter-like device activated by a data communications
link.
Teletex:
High speed Telex type service using telephone or data lines
rather than the (slower) telegraph network.
Teletext:
A one way broadcast transmission of information using part
of information using part of Television signal's spare
capacity. It enables a number of pages of information (text
and basic pictorial material to be transmitted and received
on a suitably adapted domestic TV receiver.
Telidon:
The videotex/viewdata system of Canada.
Telset:
The Finnish videotex/viewdata system.
Terminal:
A receiving device in a communication system.
Transistor:
A semiconductor device, which can act as an amplifier or
switch.
Transponder:
A transmitting-receiving system that on receipt of an
interrogation signal will transmit generated or stored
signals.
Turnkey:
A Turnkey system in a complete one, ready to work when it is
turned on.
U
User
Friendly: A description for equipment or
computer programs, which are simple and easy to use.
V
VDU:
Visual Display Unit.
Videotex:
A Disc used for the storage of audio and visual information.
Their capability for storage immense.
View
data: A generic term for British videotex type
services that utilizes public telephone lines and low cost
receivers based on the technology of TV sets.
Vista:
Name given by Bell Company of Canada to their videotex
system.
W
Winchester
(disk): A direct access storage device that
uses hard disks, which cannot be removed. The storage
capacity, speed of access and transfer rate is much greater
than floppy discs.
Word
Processor: A device incorporating a VDU,
enabling text to be entered, edited and corrected while in
preparation from a typewriter style keyboard, and then
stored for subsequent study or automatic print out via an
associated printer mechanism.
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