Archive Magazine 1995/ARCHIVE95.iso/glossary/text

Text File | 1995-08-05 | 59KB | 1,340 lines

This glossary has been created on the basis that someone may read aáword
or aátechnical term or an abbreviation within the pages of Archive
magazine and think, öWhat does XXXX mean?ò. If you think that about
aáword, look it up in this glossary. If it does not appear, please ring,
write or fax and tell us what it was that you wanted to know.

Some of the definitions will be specific to Acorn computers whereas
others are also more generally applicable.

!

!áÖá(pronounced öplingò) Aáterm used to denote an exclamation mark!

10base2áÖáAn Ethernet standard that uses BNC connectors and coaxial
cable. Also known as öthin wireò Ethernet.

10base5áÖáAn Ethernet standard that uses 9-pin D-type connectors and
special cable. Also known as öthick wireò Ethernet.

10baseTáÖáAn Ethernet standard that uses telephone connectors and
telephone cable. Also known as öCheapernetò.

A

Action buttonáÖáA button in aádialogue box which causes some action to
occur.

ADFSáÖá(Advanced Disc Filing System) This is the proprietary system used
by Acorn for organising and storing data on floppy and hard drives.

AIMáÖá(Another Image Manager) Aásuite of image processing software
produced by Delft University of Technology in the Netherlands.

ApplicationáÖáThe more general use of this word means any job for which
the computer may be used, but it has aámore specific definition. It is
used to refer to aádirectory (with aáname beginning with aáö!ò) which
contains aáprogram or programs that work under RISC OS to perform
aáparticular function. When the application is loaded, it usually makes
itself available to the user via an icon on the righthand side of the
iconbar.

Application directoryáÖáSimilar to an ordinary directory in that it
contains other files and directories but its name starts with an
exclamation mark so that when you double click on the directory, it
starts up the application rather than just opening the directory. To
open an application directory, double click with <shift> held down.

Apps iconáÖáThis is an icon that appears on the lefthand side of the
iconbar (RISC OS 3 onwards). It gives you access to aárange of
applications such as Draw, Paint, etc that are provided with each
Archimedes or RiscáPC computer.

ArchiveáÖáThe best Archimedes magazine ever, or... Aábackup of some
data.

ARMáÖá(Acorn RISC Machine) This is the original name for the 32-bit RISC
processor designed by Acorn Computers Ltd. In the name öARM Ltdò, the
company formed between Acorn and Apple, the öARMò actually stands for
Advanced RISC Machine.

ASCIIáÖá(American Standard Code for Information Interchange) This is the
most commonly used code for representing text using 8-bit binary
numbers.

ASICáÖá(Application Specific Integrated Circuit) Aásingle chip
electronic circuit that is specially designed (by computer
simulationáÖáwhat else?!) for aáparticular application, e.g. to provide
the logic needed to interface aáæ486 processor on aáRiscáPC second
processor card to the main ARM600 processor and its address and data
buses.

AssembleráÖáA compiler for converting aáprogram written in mnemonics
into aámachine code executable program.

AUNáÖá(Acorn Universal Networking) This does not apply to aáspecific
product or even aánetwork user interface but öthe overall banner for
Acornæs networking policy for the æ90s giving the strategic direction of
networking for Acorn computers.ò

B

Back iconáÖáThe icon at the top lefthand corner of aáwindow which allows
you to push the window to the back of the desktop.

BackdropáÖáThis is aádesktop background which may be aásprite or just
aápattern.

BackplaneáÖáA small printed circuit board with connectors on it that
allows you to plug in aánumber of expansion cards.

BasicáÖá(Beginners All-purpose Symbol Instruction Code) Aácommonly-used
interpreted high level language. It comes as standard on all Acorn
computers.

BaudáÖáThis is aáunit of speed for serial data transmission. 1 Baud = 1
bit per second.

BBSáÖá(Bulletin Board Service) Aábulletin board is an application run on
aácomputer which stores information and messages that can be accessed by
other computers, usually via the telephone line using aámodem. Many
bulletin boards allow aánumber of other computers to connect to the host
computer at the same time by using aánumber of different modems and
phone lines.

BIOSáÖá(Basic input/output system) This is the part of aáPC compatibleæs
operating system that is held in ROM, allowing the computer to start up
and load the rest of its operating system from disc. (cfáRISCáOS
computers where the whole of the operating system, plus aáfew extra
goodies, are held in ROM and are available at switch-on.)

BitáÖá(Binary digit) Aábit is the smallest unit of binary data. It has
two values, 0 and 1. Aágroup of 8 bits of data (referred to as aábyte)
could be used to represent aásingle character using, most commonly, the
ASCII code or it could represent (part of) an instruction that the
computer would execute at some stage or it could represent (part of)
aánumber.

Bit-mapped (graphics)áÖáIt is possible to represent aápicture on
aácomputer by using aámatrix of (coloured) dots. The resolution of
bit-mapped pictures is limited by the numbers of dots used. (This
contrasts with vector graphicsáÖásee below. For example, the Paint
application produces bit-mapped graphics whereas Draw produces vector
graphics.)

BppáÖá(Bits per pixel) The number of bits used to store the colour of
each pixel.

Bubblejet printeráÖáThis is aátype of inkjet printer where the patterns
on the paper are generated by squirting ink through aáseries of tiny
nozzles in the print head. Functionally, it is the same as an inkjet
printer.

BugáÖáError in aácomputer program.

BulletáÖáA large black dotáÖáÅáÖáused to highlight something within some
text.

BusáÖáA set of parallel wires or PCB tracks along which data is
transmitted in aácomputer system. The width of the bus refers to the
number of parallel tracks Ö the wider the bus, the faster data can be
transmitted down it.

ByteáÖáA byte refers to (usually) 8 bits of binary data stored within
aácomputeræs memory or on aádata storage medium.

C

CáÖáA high level compiled language.

C++áÖáThis is an object-oriented version of the C language.

CADáÖá(Computer Aided Design) Aácomputer-based application that allows
users to draw, design and model engineering objects.

CapsáÖáShort for Écapitalsæ. See also small caps.

Capslock keyáÖáThis is aákey on the lefthand side of the keyboard. When
it is pressed and the Capslock light comes on, all text typed into the
keyboard appears in upper case.

CaretáÖáA red vertical bar in aáscreen display that marks the point at
which text will appear if it is typed in from the keyboard.

CDáÖá(Compact Disc) Aáhigh density digital storage medium originally
intended for hi-fi sound reproduction but now applied to storage of text
and image data for various computer applications.

CDFSáÖáFiling system used for accessing CD-ROMs.

CD-ROMáÖá(Compact Disc Read Only Memory) AáCD used for the storage of
computer data. It is called aáROM to emphasise that the data on the
disc, once written in the manufacturing stage, cannot be modified.

CFSáÖá(Compression Filing System) This is aáway of accessing aádata
storage system through aácompression/decompression system such that it
is transparent to the user, i.e. the user need hardly know that the data
is being compressed and decompressed but just sees it as being read from
and written to the storage device.

Clear (files)áÖáA standard format for storing and transferring 24-bit
pictures.

CLIáÖá(Command line interpreter) Pressing <f12> allows you to type
command lines into your RISCáOS computer. These are then interpreted by
the CLI.

Close iconáÖáThe icon at the top left of each window, next to the back
icon which allows you to close the window.

CMYKáÖá(Cyan, Magenta, Yellow, Key) Aámethod of specifying colour by
using the amounts of the three primary (subtractive) colours plus the
amount of black (Key).

Colour deptháÖáEvery pixel on aácomputer screen display has its colour
defined by aácertain number of bits of data. The colour depth refers to
the range of different colours available for each pixel in aáparticular
screen mode. If aásingle bit were used, it would only allow it to be one
of two coloursáÖáusually black or white. If it were defined by two bits,
it could have 4 (22) different colours, four bits would provide (24) 16
different colours, 8-bit provides 256 (28) colours, 16-bit gives over 32
thousand colours and 24-bit allows each pixel to have any of about 16.7
million different coloursáÖáabout as much as the human eye can
distinguish. The 32-bit colour of the RiscáPC öonlyò gives 16 million
colours but the extra 8 bits can be used by the computer to produce
various different special effects.

Command lineáÖáAll Acorn computers now come with aáWIMP interface.
However, it is possible to give the computer operating system commands
by typing them in from the keyboard. If you press <f12>, aástar prompt
appears. This is the command line. You can enter commands such as
CAT<return> to get aácatalogue of the current storage device.

CompileráÖáIn aácomputer language, instructions that the programmer
enters as (vaguely) understandable words have to be translated into
series of the very simplest steps that the cpu executes. These simple
instructions are called machine code. The job of aácompiler is to take
the whole of aáprogram and convert it into aásingle machine code program
which can be executed then or at aálater stage. This contrasts with an
interpreted language in which each individual line of the program is
converted into machine code as the program is running. In aácompiled
language, you have to convert the whole program before you can run any
of it whereas in an interpreted language you can run the program at any
time, stop it, change the program and run it again. On the other hand,
interpreted programs tend to run more slowly because even if one line of
the program is run many times, it has to be interpreted into machine
code every time it is run.

Compression/decompressionáÖáThere are various mathematical techniques
which can be used to store computer data in aásmaller amount of memory
than the uncompressed data occupies. Some of these techniques are
completely reversible so that the decompressed data is identical to the
original data. However, in the case of images, it may be acceptable to
allow aádegree of degradation of the data in order to increase the
amount by which the data is compressed.

ConfigurationáÖáA collection of settings and option which describe how
the computer will operate when it is first switched on.

Control codesáÖáSpecial non-printing ASCII codes which cause aádevice to
perform some electronic or mechanical action, e.g. ASCII 10 is linefeed,
13 is aácarriage return and 12 ejects the paper or clears the screen.

CoprocessoráÖáSee Second Processor.

CPSáÖá(Characters per second) Aáway of measuring the speed of dot matrix
or inkjet printers.

CPUáÖá(Central Processing Unit) This is the electronic circuitry at the
heart of aácomputer that executes (very rapidly!) aáseries of simple
steps of reading, manipulating and writing information to and from the
computeræs RAM memory and input/output devices.

CRCáÖá(Cyclic redundancy check) This is aáway of checking for errors in
stored and transmitted data.

Crop marksáÖáIn publishing, it is important to define where aáprinted
image appears in relation to the edges of the paper. To do so, the
images can be printed on aálarger sheet of paper and markers placed on
the sheet to show where the corners of the paper will be.

CSVáÖá(Comma Separated Variables) Aástandard way in which data is stored
in aáfile where the items of data are separated by commas.

D

DatabaseáÖáThe definition of this word has changed over the years. It
used to mean aáunified collection of data files but now it tends to
refer to an integrated system of data plus the means of interrogating
and manipulating the dataáÖáeven to the extent of referring to
aádatabase language.

DaughterboardáÖáSee under Émotherboardæ.

DEBIáÖá(DMA Extended Bus Interface) This is aámeans of connecting
expansion cards to the RiscáPC. (Depending on which magazine you read,
it can support anything between eight and fourteen expansion cards!
Currently, the maximum is eight but we think it is theoretically
possible to have more.)

DebugáÖáRemove the bugs (errors) within aáprogram.

DebuggeráÖáAn application written to provide tools to aid the process of
finding errors in aáprogram.

DecompressionáÖáSee under compression.

DefaultáÖáThe standard setting or option which the computer selects
unless the user has specifically told it to do otherwise.

DeviceáÖáThis is the technical term for any information storage medium
(e.g. floppy or hard drive) or transmission system (e.g. network, modem
or printer) that can be accessed through the computer. Each currently
available device is represented by an icon at the lefthand side of the
iconbar.

DhrystonesáÖá(strictly Dhrystones/second) This is aámeans of indicating
the speed of aáprocessor by testing the number of iterations of
aáparticular test program it can perform each second. For example, the
RiscáPC 600 with aá30MHz ARM600 processor can perform about 40,000
Dhrystones/second.

Dialogue boxáÖáA window in which you are expected to select various
options and/or enter aáfilename before the computer performs
aáparticular task or operation.

DigitiseráÖáAn electronic circuit which takes an analogue signal such as
aásound of aávideo signal and turns it into digital information which
can be stored and/or manipulated within the computer and output again as
aásound or video signal.

Direct drive laser printeráÖáIn conventional laser printers, the
computer sends information to the printer about what is to be printed,
in what position and with what styles etc. The processor and memory in
the laser printer are then used to work out what dots to place where on
the paper. In aádirect drive laser, by contrast, the computer works out
what the pattern of dots should be and then sends the dot pattern down
to the printer on aáhigh speed (övideoò) parallel interface. This means
that the printer needs little or no memory of its own and the process is
faster because ARM processors tend to be much more powerful than the
processors used in laser printers.

DirectoryáÖáWhen data is stored on aástorage medium such as aáfloppy
disc, it can be grouped into directories. When the iconbar icon is
clicked, aáwindow appears showing the data in the root (i.e. main)
directory. This may be items of data (stored as files), applications or
other directories. These directories in turn can contain more
information and/or further sub-directories. This system of directories
within directories is called aáhierarchical data structure.

DitheringáÖáWhen displaying aápicture on aácomputer screen in, say,
aá256 colour mode, it is possible to give the impression of intermediate
colours by mixing dots of the different colours in different ratios.
This is done using aárandom displacement of these dots to avoid
aápatterned effect. This technique is called dithering.

DMAáÖá(Direct Memory Access) When information is being taken into
aácomputer from an external source, the cpu normally reads aálocation,
or block of locations, in the external device and writes the information
into its own RAM memory. With DMA, by contrast, the information is
written directly from the external device into the cpuæs memory without
the cpu being involved. This means that the process is much faster, as
the cpu can be doing other things while the information is being loaded
automatically into memory.

DongleáÖáThis is aásmall electronic circuit, usually held in aáplastic
connector block, that goes on the parallel port of aácomputer. It forms
an electronic Ékeyæ that allows you to use aáparticular application
(such as Impression or ArtWorks). The application checks every now and
then to see if aádongle is present and, if not, it shuts itself down and
will not restart.

DOSáÖá(Disc Operating SystemáÖábut also now used as shorthand for DR-DOS
or MS-DOS) These are the operating systems most commonly used on IBM PC
computers and compatibles. They can be used on Acorn computers by using
the PC Emulator or aáPC expansion card or, on aáRiscáPC, aáPC processor
card. They are command-line operating systems, i.e. they do not use
aáwimp interface. (For most practical purposes, there is very little
difference between DR-DOS and MS-DOS.)

Double density floppy discsáÖáDiscs that can store approximately 800Kb
of data when formatted.

dpiáÖá(dots per inch) On aádesktop printer, the text and graphics are
reproduced by rows and rows of tiny dots. The smaller the dots, the
better the definition of the resulting printout. This is usually
specified as the number of dots per inch that the printer can lay onto
the paper. The same idea is used for scanning. When scanning aápicture
or diagram, the grey level (see below) of rows of tiny areas of the
picture are assessed by the scanner. The closeness of the areas being
differentiated is measured in dots per inch.

DPMSáÖá(Display Power Management Signalling) When monitors are not being
used, it is aáwaste of energy to have them on at normal brightness.
RISCáOS 3 supports screen blanking which helps to reduce energy
consumption, but some monitors can accept special electronic signals
from aácomputer to tell it to drop into aávery low power consumption
mode if it is not being used. This signalling between computer and
monitor is not available in all monitors, although aálot of newer
monitors are beginning to provide it.

DPOBáÖá(Dual Processor Open Bus) On the RiscáPC, the processor(s) are
held on separate cards which plug into the main PCB or motherboard. It
can take two such processor cards and the dual processor open bus is
aáway of allowing two different (or similar) processors to share the use
of the computeræs memory and input/output and data storage facilities.

DRAMáÖá(Dynamic Random Access Memory) This is the most common form of
RAM memory used in computers today. ÉDynamicæ is aátechnical term which
refers to the way in which the information is stored within the chips.

DSPáÖá(Digital Sound Processing) Aáset of techniques for modifying sound
signals. It involves digitising the signals, performing various
mathematical processes on the data and then turning the resulting data
back into an analogue signal.

DTPáÖá(DeskTop Publishing) As desktop computers have increased in
processing power, it has become possible for them to handle both text
and graphics, to allow users to manipulate them on-screen and output
them to aáprinter. In this way, öbooksò can be produced on aádesktop
computeráÖáhence the term Édesktop publishingæ.

E

EconetáÖáThis is aámeans of connecting two or more computers together so
that they can exchange information and share the use of peripherals such
as printers. It is aátype of Local Area Network (LAN) developed in the
early æ80s by Acorn Computers Ltd.

Editor (1)áÖáAn application that allows you to edit the contents of
aáfile.

Editor (2)áÖáSomeone who is daft enough to take on the task of putting
together aámassive glossary!

EEPROMáÖá(Electrically Erasable Programmable Read-Only Memory) Aáform of
non-volatile memory that remains unchanged, even when the power is
switched off but which can be altered in situ by using appropriate
electronic circuitry i.e. it can be reprogrammed through software.

E-mailáÖá(Electronic mail) Aámeans communicating with other computer
users via aáLAN or through aámodem to aánational or international
computer centre.

EPROMáÖá(Erasable Programmable Read-Only Memory) Aáform of non-volatile
memory that remains unchanged even when the power is switched off but
which can be altered by using ultraviolet radiation to erase the
information and high voltages to re-program it. (But see Flash ROM and
EEPROM.)

EPSáÖá(Encapsulated PostScript) This is aátype of computer-generated
file containing the necessary PostScript commands to reproduce the
picture. It usually includes aáÉsnapshotæ of the picture that can be
used for positioning purposes. EPS is aádefined standard allowing output
from one application to be used within another.

Error boxáÖáA special type of dialogue box that gives information to
aáuser about the type of error that has occurred, requiring him to
acknowledge that it has been read.

EthernetáÖáAnother type of LAN, but much faster than Econet. It was
developed by Xerox Corporation in the late æ80s.

Expansion cardáÖá(formerly called podules or peripheral modules) An
extra circuit board fitted to your computer that will allow it to
perform various extra functions which cannot be done with software
alone.

F

FASTáÖáFederation Against Software Theft

FileáÖáA collection of information gathered together and given
aáfilename to identify it. It is stored in aádirectory in aáfiling
system.

Filer or Filing systemáÖáA system used to handle the storage of
information. The ADFS filer and the SCSI filer are the two most common
on Acorn machines.

FirmwareáÖáThis refers to software, applications and/or data which is
stored in aáROM.

Flash ROMáÖáTo change the contents of aáconventional EPROM, the chip has
to be removed and erased using ultra-violet radiation. It can then be
electrically re-programmed. Aáflash ROM, by contrast, can be
re-programmed electrically in situ, i.e. it can be reprogrammed through
software.

Floating point numbersáÖáIn order to represent aáwider range of numbers
than can be done with integers, and to represent fractions, computers
use floating point numbers. These use aánumber of bytes (usually four)
to represent the main part of the number and another byte to represent
the power of two by which the number is multiplied.

Floppy disc/driveáÖáThis is aádata storage medium consisting of
aáremovable flexible (floppy) magnetic disc in aáhard plastic case.
These discs can be inserted as required into aáfloppy drive usually
housed within the case of the computer. The most common standard of
floppy drive used now is 3╜". Some 5╝" drives are still in use but the
8" floppies have virtually all been consigned to the museum of computer
technology.

FMVáÖá(Full Motion Video) Aáterm used to refer to displaying video on
aácomputer screen at full speed. Acorn Replay provides FMV at 12.5 or 25
frames per second.

FontsáÖáCharacters on the screen and on the printed page can take on all
sorts of different shapes and styles. Aáfont is aáset of characters that
have been designed so that all the letters of the alphabet and aáwhole
range of other special characters (200 or more in aácomplete set) have
the same style. There are also sets of related fonts using the same
basic style but with the characters angled (italic) or made heavier
(bold) or both (bold italic).

FormatáÖáFormatting is preparing aáfloppy disc or hard disc ready to
receive data. Hard discs usually arrive ready-formatted. Floppy discs
may be formatted in aánumber of different ways. Not all formats of
floppy disc can be read on all computers. Without any extra software,
Acorn computers can read and write various Acorn formats as well as
aánumber of different PC and Atari formats. With extra software, other
formats, such as Apple Mac, are also accessible on Acorn computers.

FPAáÖá(Floating Point Accelerator) This is aáhardware add-on to aácpu
which enables it to do floating point calculations more quickly by doing
them in hardware rather than in software.

FPEáÖá(Floating Point Emulator) If an application requires full floating
point calculations, it is possible to run it on aácomputer that doesnæt
actually have an FPA by emulating the FPAæs functions in software.

Function keysáÖáThese are the set of twelve keys at the top of the
keyboard, all prefixed with an öFò. What they do will depend on the
application currently in use.

G

GbáÖá(Gigabyte) Approximately one thousand million bytes of computer
data. (Actually, it is 1K ╫ 1K ╫ 1Kb = 230 = 1024 ╫ 1024 ╫ 1024 =
1,073,741,824 bytes.)

GenlockáÖáThis is aádevice which enables the output from the computeræs
video system to synchronised with aánormal video signal so that
computer-generated text and graphics can be superimposed on the video
signal.

GIF (files)áÖ (Graphics Interchange Format)áA standard format for
storing and transferring bit-mapped graphics.

Grey levelsáÖáA photograph may have some areas completely white and some
completely black. Most areas, however, will be somewhere in between. If
you wish to represent that picture electronically, you have to judge the
Égreynessæ of each part of the picture. If you represent this on aáscale
of 0 to 15 (16 grey levels), it will not give such aáfaithful
representation of the picture as if 64 or 256 grey levels were used.
However, the more grey levels used to represent each point on the
picture, the more data is being used. For example, in 256 grey levels,
aáfull A4 picture scanned at 400 d.p.i. could occupy as much as 12Mb!

GUIáÖá(Graphical User Interface) At one time, virtually all interaction
between humans and computers was done on the basis of the human typing
words or codes into some form of keyboard, and the displays were only
able to show text characters, not graphical images. As computing power
became more accessible, it became possible to provide aáform of
interaction that was based far more on pictures (icons) within windows
on the screen. The user could then indicate choice and initiate action
by using aámouse or trackerball to move aápointer around the screen.

H

Hard driveáÖáA case containing aánumber of rigid metal discs covered
with magnetised material that can be used to store data; it usually has
aácapacity of several megabytes or even gigabytes.

HDáÖá(Hard drive)

HierarchicaláÖáThis is usually used in referring to the data structure
on storage mediaáÖásee Édirectoryæ.

High level languageáÖáThis refers to aácomputer language in which
instructions that the programmer enters are each converted into aánumber
of machine code instructions by aácompiler or an interpreter. Basic,
Fortran, C etc are high level languages, whereas assembly language is
aálow level language.

High density floppy discsáÖáDiscs that can store approximately 1,600Kb
of data when formatted under ADFS or up to 1,440Kb when formatted under
MSDOS.

HSVáÖá(Hue Saturation Value) This is aácolour-picking system for use in
DTP.

HourglassáÖáThis is the egg-timer thing that appears on the screen all
too often, telling you that the application is taking aálong time to do
something and that it doesnæt want interrupting.

I

IconbaráÖáThe strip along the bottom of the computer screen that
contains icons for devices (to the left) and applications (to the right)
that are currently available to the user.

IconsáÖáSmall pictures representing devices, files, directories,
applications, etc.

IDCáÖá(Insulation Displacement Connector) This refers to aáconnector
where the connection between the contacts and the individual wires is
made by squeezing aárow (or usually two rows) of sharp metal teeth onto
aáribbon cable so that the teeth cut into the insulation and make
contact with each individual wire.

IDEáÖá(Integrated Drive Electronics) An electronic standard method of
connecting one or two hard drives to aácomputer system. The standard was
set up to provide aásimpler and cheaper means of connecting hard drives
to IBM and compatible computers than was currently available.

Image processingáÖáIf an image is stored on aácomputer as binary data
(such as aásprite file) it is possible to manipulate the data
mathematically to enhance, distort, translate or otherwise modify the
picture in controlled ways.

Inkjet printeráÖáThis is aátype of printer where the patterns on the
paper are generated by squirting ink through aáseries of tiny nozzles in
the print head.

Input focusáÖáThe input received from the keyboard can be directed to
one and only one window at aátime. The window currently receiving
information from the keyboard is said to have the input focus. This is
indicated by the title bar of the window changing from grey to yellow.

ISA BusáÖá(Industry Standard Architecture) This is aáöstandardò
expansion interface as used on PC compatibles.

InterlaceáÖáBuild up aápicture on aámonitor screen using two passes,
each displaying alternate lines, the aim being to reduce flicker
effects.

InterpreteráÖáA type of high level language in which each instruction is
converted into machine executable code line by line, as the program
proceeds. (See Écompileræ for more explanation.)

I/OáÖá(Input/Output)

IOCáÖá(Input/Output Controller) The I/O chip used on pre-RiscáPC Acorn
computers was called IOC.

IOMDáÖá(Input Output Memory Device) This is aácomputer chip designed by
ARM Ltd which allows ARM processors to control input/output devices and
to access memory.

J

JPEGáÖá(öJoint Picture Encoding Groupò or, some say, öJoint Photographic
Experts Groupò) It is aábody set up in the USA to produce an industry
standard for still picture compression and storage. The theory is that,
with an agreed file format, one companyæs decompression program can read
the files produced by someone elseæs compression program.

K

KbáÖá(Kilobyte) Approximately one thousand bytes of computer data.
(Actually, it is 210 = 1024 bytes.)

KerneláÖáThe main part of the RISCáOS operating system.

KerningáÖáThis refers to the spacing between individual pairs of
characters. To improve the look of printed text, certain character pairs
need to be printed closer together than others. It can also refer to
shifting characters up or down relative to one another.

L

LANáÖá (Local area network) Aágeneral term for aámeans of connecting
computers together on one site so that they can share information.
Econet and Ethernet are examples of LANs.

LeafnameáÖáThe last part of the pathname, i.e. the name of the file or
directory being referred to.

Letter box modeáÖáThere are some monitors that were never designed to
display screen modes of the like of Acorn modes 12, 15, etc. Some are
completely incapable of displaying them whereas others can display them
but with aásomewhat reduced vertical height, the shape being likened to
the mouth of aáletter box.

LinkeráÖáWhen using aácompiler, this is the program that joins the
object code from various sub-programs, including the library routines,
to form the final executable machine code program.

LispáÖáA high level computer language often associated with artificial
intelligence programming.

Low level languageáÖáA language which involves programming the computer
at the level of one written instruction (or mnemonic) for each machine
code instruction.

M

MbáÖá(Megabyte) Approximately one million bytes of computer data.
(Actually, it is 1K ╫ 1Kb = 220 = 1024 ╫ 1024 = 1,048,576 bytes.)

MEMCáÖá(MEMory Controller) The chip used on pre-RiscáPC Acorn computers
to control the way the cpu and video controller accessed the computeræs
memory.

MHzáÖá(MegaHertz or Millions of cycles per second) This is most often
used to refer to the speed of aácomputeræs processor or memory. e.g. the
RiscáPC 600 has aá30MHz processor which means that it can carry out 30
million program steps each second.

MidiáÖá(Musical Instrument Digital Interface) Aádefined standard for the
physical link-up between musical instruments and controllers, and also
the format of the data transmitted.

MIPSáÖá(Million Instructions Per Second) Aámeasure of how fast aácpu is
running in terms of the number of instructions it can execute each
second.

MnemonicáÖáA code used in an assembler to represent aámachine code
instruction.

ModeáÖáSee screen mode.

ModemáÖá(An abbreviation for modulator-demodulator) It is aádevice which
takes aáserial stream of computer data and converts it into audible
tones that can be transmitted down aátelephone line that was originally
design for carrying voice information. It enables two computers to
exchange data at aádistance via the telephone system.

MonitortypeáÖáA computer variable that determines which ranges of screen
modes the computer will attempt to display on your monitor.

MotherboardáÖáThe main circuit board of aácomputer is sometimes referred
to as aámotherboard, especially when, as in the RiscáPC, many of the
functional parts of the computer are on separate PCBs (sometimes called
daughterboards) that are plugged into the main or motherboard.

MPCáÖá(Multimedia Personal Computer) The östandardò multimedia computer
used in the PC world.

MPEGáÖá(Motion Picture Experts Group) Aágroup of technologists who are
establishing an international standard for the compression of moving
video and its associated audio.

MTBFáÖá(Mean Time Between Failure) An indication of how long, on
average, it will be before aámachine goes wrong.

MultimediaáÖáA blend of communications elements, usually computer-based,
which allow information in such forms as sound, speech, text, still
pictures, moving images and animations to be presented to the user so
that it can be accessed in an interactive way, the user selecting which
piece(s) of information to pursue.

MultisessionáÖáInformation stored on aáPhotoCD can be added to at
aálater date with the appropriate (very expensive) equipment. In order
to read all the information on these CDs, you need aáCD-ROM drive that
is multisession capable.

Multisync monitoráÖáSome monitors are designed (for cheapness) that only
display in certain modes. Others can display aárange of different
modesáÖáthey can synchronise onto aárange of different frequency signals
and are therefore called Émultisyncæ monitors.

MultitaskingáÖáAn operating system like RISCáOS is capable of running
aánumber of different tasks all at the same time. This is multitasking.
(Actually, I think itæs aábit of aácon. The cpu can really only does one
job at aátime but what it does is to do aálittle bit of each task every
fraction of aásecond.)

N

NetworkáÖáA means of connecting aánumber of computers together so that
they can share data and the use of peripherals.

NFSáÖá(Network Filing System) AáRISCáOS filing system that uses Acornæs
Econet network system.

O

Obey fileáÖáA file of commands prepared for execution by the RISCáOS
command line interpreter.

Object codeáÖáthe machine-executable code produced by aácompiler.

Object orientedáÖáThe approach used in conventional programming is to
have aánumber of procedures or routines which can work on some data.
There is no conceptual connection between the data and the operations
which are performed on it. In contrast to this, object-oriented
programming works on aáconcept of objects, which consist both of data
fields (similar to aástructure in C) and of aálist of methods which may
be applied to that data. For example, you could define an object point
(with data x and y, both integers), and define aámove method on it to
change these fields.

One of the most useful concepts which may be derived from this is
inheritance Ö an object can be defined as aásub-type of another object,
and in doing so inherit all its methods (and data fields), but may also
add its own. As an example, you could define aácircle object with data x
and y (inherited from the parent point object) but with another data
field, radius. Similarly, the circle would inherit the move method
(which would not have to be rewritten), but could also have aáresize
method added to it.

The result of these changes in approach is that it is often easier to
implement large programs, since it is harder to get confused about how
aápiece of data should be used, and less code needs to be rewritten.
Object-oriented languages include Modula-3, C++ and Objective C.

(Well, you wanted to know what it meant, didnæt you?! Thanks to Andrew
Garrard for that definition. Ed.)

OCRáÖá(Optical Character Recognition) Computers can be trained to
examine the shapes of typed or printed characters and work out what the
letters, words and sentences are. So, combined with aáscanner or camera
and digitiser, the computer can Éreadæ text off books and paper. Because
of the difficulty of being 100% accurate, it may take as long to edit
out the mistakes as to type the text in from scratch, so OCR programmers
are fighting all the time to make their programs more and more accurate
without becoming too slow for practical use. This facility will become
more viable as we get progressively faster processors.

OLEáÖá(Object Linking and Embedding) This is aámeans of linking data of
different types (e.g. text, drawfiles, sprites, etc) within one document
so that each element can be easily edited. Double-clicking on an element
brings up the appropriate editing application (Draw, Paint, ArtWorks,
etc) to allow you to make the necessary changes without having to export
and then re-import the data.

Operating systemáÖáThis is the set of öhouse-keepingò programs within
aácomputer which handle all the input/output, filing systems, etc. All
modern Acorn computers come with the RISCáOS operating system as
standard (stored in ROM) but it is possible to use alternative operating
systems such as DR-DOS and MS-DOS by adding the appropriate software or
hardware.

Option iconáÖá An icon that appears in aádialogue box. Each time you
click on it, you will switch aáparticular option on or off.

OS áÖá(Operating System Ö See above)

OS graphic unitáÖáA unit for defining graphics under RISCáOS so that
they are independent of the current screen mode. There are nominally 180
OS graphics units to the inch.

Outline fontsáÖáThese are fonts that are described mathematically by
using equations to define the curves that make up the outline of the
characteræs shape. Using these equations, it is relatively simple to
work out how to display any font at any size, either on the screen or on
aáprinter where the shape has to be reproduced as aáseries of dots.

P

PaletteáÖáThis is aáset of colours used for the desktop display. If the
display has, say, 256 colours, the palette determines which actual
physical colour is displayed on the screen for each of the colour
numbers from 0 to 255.

PaneáÖáA dialogue box that is attached to aáparticular window, e.g. the
toolbox at the side of aáDraw window.

ParalleláÖáA device or communication channel is said to be parallel if
the data is sent several bits at aátime down several parallel
wiresáÖáthe printer port sends eight bits of data at aátime.

Parallel processoráÖáIn some computers, such as the RiscáPC, it is
possible to have two processors working side-by-side, sharing the use of
memory, data storage and peripheralsáÖásuch processors are referred to
as Éparallel processorsæ.

Parent directoryáÖáThe directory within which the directory you are
currently dealing with is stored. (It is the opposite of
aásubdirectory.)

ParityáÖáA method of checking for errors in transmitted or stored data.
An extra bit (the parity bit) is added to each ASCII character so that
the number of É1æ bits is always odd (or always even).

PathnameáÖáThis is the full name of aáfile or directory including the
filing system, disc name (or number) and the sequence of directories
that have to be opened to access that particular file or directory e.g.
SCSI::Paul105.$.Archive.Bits.!Glossary

PBM (files) Ö (Portable Bit-Maps)áA standard format for storing and
transferring bit-mapped graphics.

PCBáÖá(Printed Circuit Board) Aápiece of insulating material covered
with conducting tracks, used to interconnect electronic components to
make up an electronic circuit.

PC CardáÖáA PC processor on aáseparate card that can be used as aásecond
processor in aáRiscáPC.

PC EmulatoráÖáA software application that can work within RISC OS or as
aáseparate program taking over the whole of the computeræs processing
power which enables the computer to pretend to be an IBM PC and run
(most of) the programs that are written to run under MS-DOS or DR-DOS on
those computers.

PC Expansion CardáÖáAn expansion card containing aáPC processor plus
memory plus some I/O capability that can allow PC programs to be run
within the RISCáOS environment.

PentiumáÖáThis is aá32-bit cpu with aá64-bit data bus produced by Intel
Corporation.

PeripheraláÖáAn item of hardware such as aámonitor or printer that can
be connected to your computer.

PinboardáÖáThis is an application that makes use of the blank areas of
the desktop. You can 'stick' various files or applications onto it so
that they are easily accessible without having the filer windows open
for each of the directories in which they are stored.

PixeláÖáA tiny point of light and colour which is the smallest picture
element in aávideo or computer image. The more pixels making up the
image, the better the resolution.

PoduleáÖáSee 'expansion card'.

Pop-up menuáÖáA menu available by clicking an icon in within aádialogue
box. The icon is often placed alongside aádisplay showing the current
setting of that option.

PostScriptáÖáA page description language used in some laser printers and
imagesetters. PostScript is aádefined standard so that applications
using it can produce output that can be printed on any PostScript
device.

Printer driveráÖáThis is the program that converts aádocument or file
created by an application into information that your particular printer
needs to reproduce the information on paper. The term can be extended to
öprintingò aáfile or document via aáfax modem. The output is in the form
which aáfax modem can then transmit, the printed output appearing on the
fax at the other end of the phone line.

Printer manageráÖáAn application that oversees the printing process.

PrologáÖáA high level computer language often associated with artificial
intelligence programming.

ProcessoráÖáSee CPU.

PRMáÖá(Programmers Reference Manual) Aáset of manuals covering many
highly technical programming details of the RISCáOS operating system.

Public Domain (PD)áÖáThere are aánumber of enthusiastic people who
produce programs and clipart which they want to make freely available
for other people to useáÖárather than trying to make money by selling
them. The material is distributed at cost by various individuals and
agencies. There are quite aánumber of PD libraries dealing with material
for Acorn computers. (Norwich Computer Services currently runs one such
library, part of which raises money for charity.)

Q

QuitáÖáClose aáfile or application so that its window(s) disappear from
the screen and, in the case of an application, it disappears from the
iconbar.

Qwerty (keyboard)áÖáLook at the six characters at the top left of your
keyboard and youæll see what itæs called aáqwerty keyboard. (In France
it would be AZERTY and in Germany QWERTZ.)

R

Radio iconsáÖáA group of buttons within aádialogue box, only one of
which can be selected at aátime.

RAMáÖá(Random Access Memory) This is the place within the computer where
information is stored on aátemporary basis. When the computer is
switched off, information in RAM is lost.

RAM discáÖáPart of the computeræs RAM memory can be set aside so that
the user can store files and data on aátemporary basis during aácomputer
session. The information is accessed through aáfiler in the same way
that you would access an external storage medium such as aáfloppy or
hard drive.

Relocatable moduleáÖáA section of computer code that can be used to
extend the facilities of the operating system and which can then be used
by any application running in the computer.

Removable hard disc driveáÖáThis is cross between aáhard drive and
aáfloppy drive. It uses aásolid metal disc so that it can store large
amounts of data (currently up to 270Mb on aásingle disc) but the disc is
held in aáplastic case like aáthick floppy disc. The cartridge can be
taken in and out of the drive so that aánumber of discs can be used for
different purposes, and the data can be transferred easily from one
computer to another.

ResolutionáÖáThe complexity of detail that can be seen on aácomputer
screen or aáprinter can be specified in terms of resolution, i.e. the
numbers of dots per inch.

ResourcesáÖáThe various programs and data files which an application
uses to perform its task.

RGBáÖá(Red Green Blue) Any colour can be made up of aácombination of
different amounts of light of these three primary colours. So colour
monitors (RGB monitors) use sets of three coloured phosphor dots of
these three colours.

RIPáÖá(Raster Image Processor) This is aádevice used in the printing
industry to produce aávery high resolution output.

RISCáÖáThis is an acronym for Reduced Instruction Set Computer.
Companies like Acorn (and many years later, Apple, though not yet,
apparently, Intel) realised that the trend to more and more complex
computer processors wasnæt necessarily the best way to increase the
overall speed of computer processing. These complex processors were
spending the majority of their time doing simple tasks anyway. Acorn
made the processors simpler, which meant they could work much faster
doing the simple jobs like pushing text around and drawing dots on the
screen. This is partly why RISC processors are so well-suited to DTP
applications. (N.B. This explanation is aágross over-simplification
which doesnæt do justice to the brilliance of the designers of the Acorn
RISC processors!)

RISCáOSáÖáThis is the operating system used on Acornæs RISC-based
computers.

RISC_OSLibáÖáA library supplied with Acornæs ANSI C compiler designed to
help you program applications that run in the RISCáOS desktop.

RMAáÖá(Relocatable Module Area) The area of RAM set aside for the
program modules used by different applications.

ROMáÖá(Read-Only Memory) Aáform of non-volatile memory that remains
unchanged even when the power is switched off and which cannot (usually)
be altered. (But see Flash ROM and EPROM.)

Root directoryáÖáThe main directory of aástorage device which contains
all other directories and files and which is displayed when the iconbar
icon of the device is clicked.

RS232/RS423áÖáThese are two different (but similar) electrical standards
for the transmission of serial data.

S

SampleráÖáAn add-on that takes aásound signal as input and turns it into
digital data that can stored and/or manipulated within the computer and
then be output again through aáDAC (digital to analogue converter).

ScanneráÖáAn add-on that enables the user to read visual images into the
computer from originals such as photographs and books.

SCARTáÖá(Syndicat des Constructeurs dæAppariels de Radio et de
TelevisionáÖáwell, you wanted to know, didnæt you!) Aámeans of
connecting computers, video recorders, etc to televisions and monitors
using standard connections.

!ScrapáÖáA special directory on which RISCáOS makes available for
applications to use as temporary storage space. Use of this directory is
under the control of the application and the user is normally unaware of
it.

Screen blankingáÖáWithin RISCáOS 3 is an optional facility (set in the
configuration) which switches the screen to black after aáuser-definable
length of time if the computer is not being used. As soon as aákey is
pressed or the mouse is moved, the screen returns to normal. This
reduces the likelihood of monitors having patterns Éburned inæ to the
face of the tube (and reduces the power consumption of the monitor to
some extent).

Screen modeáÖáInformation can be displayed on TV or monitor screens in
aánumber of different formats. The numbers of pixels that make up the
screen may be different (from, say, 480 ╫ 512 to 1600 ╫ 1200 or more)
and the colour depth of each pixel may vary. The amount of memory used
to display the screen will increase as both the number of pixels and the
colour depth are increased. There is aátrade-off between the two as the
amount of video memory is usually limited. Aáparticular size and colour
depth is referred to as aáscreen mode.

Scroll arrowáÖáThe arrows within aáwindow that are used to allow you to
scroll through aádocument or list or to move around the contents of
aáwindow that is too big to display in the current size of window.

ScrollingáÖáIf aáfile or document is too large to be displayed on the
screen all at once, it is displayed in aáwindow with scroll bars and
scroll arrows so that you can move around and view different parts of it
as necessary.

SCSIáÖá(Small Computer Systems Interface) This is an agreed standard
system for communicating data between computers and data storage and
acquisition devices, the data being transmitted along parallel data
paths. It is commonly used to link aácomputer to hard drives, CD-ROMs
and/or scanners, but it can also be used to link computers together,
subject to the limitation that you can only link aátotal of eight
different Édevicesæ together.

SCSIFSáÖáA RISCáOS filing system used for communicating with devices
attached to the SCSI interface.

Second processoráÖáIn computers such as the RiscáPC it is possible to
have more than one processor working together sharing memory, data
storage and peripherals. In the RiscáPC, the ARM610 takes charge when
the computer is first switched on and it then allows the other processor
(the Ésecond processoræ) access to memory etc.

Select boxáÖáA rectangular box used to outline an area within which any
objects are selected.

Self-testáÖáWhen aácomputer is switched on, it runs through aáseries of
tests to check, as far as it is able, that it is functioning correctly.
In aáRISCáOS 3 (or later) computer, if any of these self-tests fails, it
will usually issue some sort of error message. If the system has not
managed to get as far as producing aáworking display on the VDU, it will
send aácoded message about the likely error by flashing the LED on the
floppy drive.

SerialáÖáA device or communication channel is said to be serial if the
data is sent sequentially, one bit at aátime, as opposed to being sent
several bits at aátime down parallel wires.

ShovelwareáÖáThis is aáderogatory term for software and other data of
inferior quality that is used to Épack outæ aáCD-ROM and make it up to
600Mb, or whatever, to convince the potential purchaser that the disc is
worth buying.

ShutdownáÖáA menu option on the task manager iconbar menu which Éclears
upæ the computer prior to switching it off. It can also be done by using
<ctrl-shift-f12>.

SIMMáÖá(Single In-line Memory Module) An industry standard plug-in
memory card as used in the RiscáPC, for example.

SliceáÖá(Single Layer Item of Computer Expansion!) The name applies to
aásingle extra layer of case in aáRiscáPC. It includes aánew backplane
with two more slots than previously and four locking pins longer than
the ones they replace.

SmalltalkáÖáA high level computer programming language that allows you
to use object-oriented techniques.

SOHO (market)áÖá(Small Office Home Office) Aádefined market into which
companies try to sell their computer goodies.

Source codeáÖá the name given to the program written in aáhigh level
language which is converted by aácompiler into machine executable code.

SpriteáÖáA graphic made up of coloured pixels.

Sprite pooláÖáAn area of memory used by RISCáOS for storing sprites.

SQLáÖá(Structured Query Language) Language for extracting information
from aádatabase.

SubdirectoryáÖáWithin any directory, you can store files and other
directories. Aádirectory that appears inside another directory is
referred to as aásubdirectory.

SVGAáÖá(Super VGA) An enhanced colour graphics standard from the PC
worldáÖá1024╫768.

System application (!System)áÖáAn application that contains many of the
resources that can be used by any or all other applications.

System discáÖáA floppy disc containing aácopy of !System.

T

TapestreameráÖáComputer data has, for many years, been stored on
magnetic tape. This is aábasically inefficient method in the sense that
if you are at one end of the tape and the data you want is at the other
end, it can take aálong time to reach the information. However, it is
very efficient in the sense that the medium, magnetic tape, can be very
inexpensive per megabyte. Aátapestreamer is aáglorified (video) tape
recorder controlled by the computer and is used mainly for backup
storage purposes.

Task manageráÖáThis is the Acorn icon at the far right of the iconbar.
It is an application that controls the allocation and use of memory
within the computer.

TCP/IPáÖá(Transfer Control Protocolá/áInterface Protocol) This is
aástandard protocol for transferring data between different computers on
aáLAN or via modem link.

TemplateáÖáA set of windows and dialogue boxes that have been designed
for use within an application.

TIFF (files)áÖá(Tagged Image File Format)áA very versatile format for
storing and transferring bit-mapped graphics.

Title baráÖáThe bar along the top of aáwindow that contains the name of
that window.

TLBáÖá(Translation Look-Aside Buffer) This is part of an ARM processor
which helps it to access different areas of memory more quickly.
Basically, itæs the bigger the buffer the better!

Toggle size iconáÖáThe icon at the top righthand corner of aáwindow that
is used to extend and contract aáwindow between its maximum size and the
size and position to which you last reduced it.

TokenisedáÖáWhen aáBasic program is stored, it is usually stored with
each keyword represented by aásingle byte rather than as aástring of
ASCII codes. These single bytes are referred to as tokens.

ToolboxáÖáA window or pane of tool icons. It may be free-standing or
attached to another widow.

ToneráÖáThis is the fine powder used in aálaser printer (or
photocopier).

TPIáÖá(Tracks per inch) This is one way of specifying the amount of data
you can store on your floppy discs, e.g. 800Kb 3╜" discs (DD) are
135tpi.

TrackingáÖáIn some applications, the spacing between individual letters
within aáblock of text can be controlledáÖáthis is called tracking. If
the tracking is changed, the spacing between all the characters is
increased or decreased. This is distinct from kerning which relates to
the spacing between individual pairs of characters.

Transparency maskáÖáAn optional part of aásprite that defines which
pixels of that sprite are transparent.

TRMáÖá(Technical Reference Manual) Term used to refer to the optional
hardware manual for Acorn computers.

TSVáÖá(Tab Separated Variables) Aástandard way in which data is stored
in aáfile where the items of data are separated by tab characters.

U

U think of something Ö I canæt!

V

VapourwareáÖáA derogatory term for software that is being advertised but
isnæt actually availableáÖá it is often said to be available öreal soon
nowò!

VDUáÖá(Visual Display Unit) The monitor or television used to display
the output of the computer.

Vector graphicsáÖáIt is possible to represent aápicture on aácomputer by
using aáseries of lines, shapes, characters etc. When such pictures are
printed, the resolution of the pictures produced is only limited by the
resolution of the output device. (This contrasts with bit-mapped
graphicsáÖásee above. For example, the Draw application produces vector
graphics whereas Paint produces bit-mapped graphics.)

VESAáÖá(Video Electronics Standards Association)

VGAáÖá(Video Graphics Adapter or Array) Aágraphics standard from the PC
worldáÖá640╫480.

VIDC20áÖá(Video Controller) The video and audio controller designed by
ARM Ltd and used in the RiscáPC.

Virtual memoryáÖáA method by which an application, which requires more
RAM memory than aácomputer actually has, can still operate. It is done
by using parts of aáhard driveæs memory as an extension of the real
memory, the information being swapped in and out by the operating
system, as and when it needs to be accessed by the application.

VirusáÖáA computer program which can replicate itself (unbeknown to the
user) in various storage devices and in several places on one storage
device. As discs are taken from one computer to another, the virus can
be spread to more and more computers. Often, the effect of these
programs is to cause malicious damage to data within the computer
system.

VRAMáÖá(Video RAM) This is aábank of high speed RAM used to store the
information for the screen display. It can usually (as in the RiscáPC)
be accessed by the computeræs processor and by the video controller at
the same time. The computer accesses it as necessary to change the
screen display and the video controller accesses it on aácontinuous
basis to constantly generate the signals the monitor needs to display
the information set up by the computer.

W

WeightáÖáThis refers to the density of the characters within aátypeface
Ö e.g. bold, light, extra, demibold, extrabold, etc.

WIMPáÖá(Windows, Icons, Menus and Pointer) Aámethod by which aáuser can
interact with aácomputer without having to learn lots of special words.
It provides aámuch more intuitive Éviewæ of the computer and its
facilities than non-WIMP operating systems provide.

WinchesteráÖáOld-fashioned term for aáhard disc, named after the
inventors of the technology.

Window manageráÖáThis is the official name for the RISCáOS WIMP system.

WordáÖáA group of bytes considered by the cpu to be aáunit of data. In
Acorn 32-bit computers, aáword is four 8-bit bytes.

WPáÖá(Word-Processing)áÖáIn the early days of microcomputers,
word-processing was limited to handling text to create documents. These
days, however, many of the programs that are referred to as
word-processors can also handle pictures, so the distinction between WP
and DTP is becoming less clear.

Writable iconáÖáA submenu into which you can type some information such
as aáfilename.

Write-protectáÖáOpen the tag at the corner of aáfloppy disc in order to
protect the contents from being edited or accidentally deleted.

WYSIWYGáÖá(What You See Is What You Get) In the days of text-based
word-processing, the screen display would only gave an indication of
which words would appear on aágiven printed page but often not much more
than that. WYSIWYG describes aásystem where the screen display shows the
size and positioning of all the text (and graphics) exactly as it will
appear on the printed page.

(WITHIWIG is another version of WYSIWYG but said with tongue in cheek.
It applies to those applications which are not quite what they claim!)

WhetstonesáÖáThis is aáfloating point version of the Dhrystones test.

X

XGAáÖá(Extended Graphics Adapter or Array) The definition varies (as
well as the name) depending which book you read but it is roughly 1024 ╫
768 in lots of colours!

Y

Yádo we have to have something for every letter?

Z

ZzzzáÖáThis is what happens to anyone who tries to read right the way
through aáglossary like this one!





Sources

I acknowledge, with grateful thanks, the many Archive subscribers who
have contributed ideas and definitions for this glossary. I would also
like to acknowledge various books I have consulted that have been most
useful in compiling this glossary:

Acorn RISCáOS Style GuideáÖáAcorn Computers LtdáÖá1-85250-148-0

Acorn RiscáPC Welcome GuideáÖáAcorn Computers LtdáÖá1-85250-143-X

Acorn User MagazineáÖávarious issues

Archimedes World MagazineáÖávarious issues

DTP at aáGlanceáÖáRob PickeringáÖáBookmark PublishingáÖá1-85550-002-7

RISCáOS First StepsáÖáAnne RooneyáÖáDabs Press Ö 1-870336-83-6.