Dictionary of Computing - 5th Edition

request for comment /r kwest fəkɒment/ noun full form of RFC

request to send /r kwest tə send/ noun a signal used in an RS-232C serial port to control the flow of data from another device, e.g. a modem. When the computer is ready to receive more data, it sends a RTS signal to the modem that replies with a signal on the CTS pin of the RS-232C connector and then sends the next batch of

data to the computer. Abbr RTS

request to send signal /r kwest təsend s n(ə)l/ noun a signal sent by a

transmitter to a receiver asking if the receiver is ready to accept data, used in the

RS232C serial connection. Abbr RTS requirements /r kwa əmənts/ noun

things which are needed Memory requirements depend on the application software in use.

re-route /ri ru t/ verb to send something by a different route

rerun / ri r n/ verb to run a program or

a printing job again

rerun point / ri r n pɔ nt/ noun a place in the program from where to start a running again after a crash or halt

res /rez/ noun same as resolution resample /ri sɑ mp(ə)l/ verb to change the number of pixels used to make up an image

resave /ri se v/ verb to save a document or file again It automatically resaves the

text.

rescue dump / reskju d mp/ noun data automatically saved on disk when a computer fault occurs. The rescue dump describes the state of the system at that time, and is used to help in debugging. research /r s tʃ/ noun scientific investigation carried out in order to learn new facts about a field of study

research and development /r s tʃ ən d veləpmənt/ noun full form of R &

D

reserved character /r z vdk r ktə/ noun a special character which is used by the operating system or which has a particular function to control an operating system and cannot be used for oth-

er uses

reserved sector /r z vd sektə/ noun the area of disk space that is used

only for control data storage

reserved word /r z vd w d/ noun a word or phrase used as an identifier in a programming language. It performs a par-

ticular operation or instruction and so cannot be used for other purposes by the pro-

grammer or user.

reset / ri set/ verb 1. to return a system to its initial state, in order to allow a program or process to be started again 2. to set a register or counter to its initial state

When it reaches 999 this counter resets to zero.

COMMENT: Hard reset is similar to soft reset but with a few important differences. Hard reset is a switch that directly signals the CPU, while soft reset signals the operating system; hard reset clears all memory contents, while a soft reset does not affect memory contents; hard reset should always reset the system, while a soft reset does not always work if the operating system has been upset in a signifi-

cant way.

reset button / ri set b t(ə)n/, reset key noun a switch that allows a program

to be terminated and reset manually reshape handle / ri ʃe p h nd(ə)l/

noun (in a GUI) a small square displayed on a frame around an object or image that a user can select and drag to change the shape of the frame or graphical object resident / rez d(ə)nt/ adjective referring to data or a program that is always in

a computer

resident engineer / rez d(ə)nt end'n ə/ noun an engineer who works perma-

nently for one company

resident fonts / rez d(ə)nt fɒntz/ plural noun font data which is always present in a printer or device and which

does not have to be downloaded

resident software / rez d(ə)ntsɒftweə/ noun a program that is held per-

manently in memory (whilst the machine is on)

residual /r z djuəl/ adjective remaining after the rest or the others have disap-

peared or have been dealt with

residual error rate /r z djuəl erəre t/ noun the ratio between incorrect and undetected received data and total data

transmitted

residue check / rez dju tʃek/ noun an error detection check in which the received data is divided by a set number and the remainder is checked against the required remainder

resist /r z st/ noun a substance used to protect a pattern of tracks on a PCB, which is not affected by etching chemicals.

photoresist

resolution / rezə lu ʃ(ə)n/ noun the number of pixels that a screen or printer

can display per unit area The resolution of most personal computer screens is not much more than 70 dpi (dots per inch).

Also called res

‘Group IV fax devices can send a grey or colour A4 page in about four seconds, at a maximum resolution of 15.7 lines per millimetre over an Integrated Serv-

ices Digital Network circuit.’ [Computing]

resolving power /r zɒlv ŋ paυə/ noun a measurement of the ability of an optical system to detect fine black lines on a white background, given as the number of lines per millimetre

resonance / rez(ə)nəns/ noun a situation in which a body oscillates with a very large amplitude because the frequency applied to it is the same as its natural frequency

resource /r zɔ s/ noun a useful device, product, program or graphic object

resource allocation /r zɔ sləke ʃ(ə)n/ noun the process of divid-

ing available resources in a system between jobs

resource fork /r zɔ s fɔ k/ noun (in an Apple Macintosh) one of two forks of a file. The resource fork contains resources such as fonts, codes or icons that the file needs.

resource interchange file format

/r zɔ s ntətʃe nd' fa l fɔ m t/ noun

full form of RIFF

resource sharing /r zɔ s ʃeər ŋ/ noun the use of one resource in a network

or system by several users

response frame /r spɒns fre m/ noun a page in a videotext system that al-

lows a user to enter data

response position /r spɒns pəz ʃ(ə)n/ noun the area of a form that is to

be used for optical mark reading data response time /r spɒns ta m/ noun

1. the time which passes between the user starting an action, by pressing a key, and the result appearing on the screen 2. the speed with which a system responds to a stimulus

restart /r stɑ t/ verb to start something again First try to restart your system. restore /r stɔ / verb to put something back into an earlier state

‘…first you have to restore the directory that contains the list of deleted files’ [Personal Computer World]

restrict /r str kt/ verb to keep something within a certain limit

restriction /r str kʃ(ə)n/ noun something that restricts data flow or access

result /r z lt/ noun the answer or outcome of an arithmetic or logical operation result code /r z lt kəυd/ noun a message sent from a modem to the local computer indicating the state of the modem

resume /r zju m/ verb to restart the program from the point where it was left, without changing any data

retrain / ri tre n/ verb to re-establish a better quality connection when the quality of a line is very bad

retrieval /r tri v(ə)l/ noun the process of searching, locating and recovering information from a file or storage device

retrieve /r tri v/ verb to extract information from a file or storage device

These are the records retrieved in that search.

retro- /retrəυ/ prefix relating to an earlier time, state, or stage of development retrofit / retrəυ f t/ noun a new device or accessory added to an existing system to upgrade it

retrospective parallel running

/ retrəυspekt v p rəlel r n ŋ/ noun running a new computer system with old data to check if it is accurate

retrospective search

/ retrəυspekt v s tʃ/ noun a search of documents on a certain subject since a certain date

return /r t n/ noun 1. an instruction that causes program execution to return to the main program from a subroutine The program is not working because you missed out the return instruction at the end of the subroutine. 2. a key on a keyboard used to indicate that all the required data has been entered You type in your name and code number then press return. 3. the indication of an end of line (in printing) return address /r t n ə dres/ noun the address to be returned to after a called routine finishes

COMMENT: The return address is put on the stack by the call instruction and provides the address of the instruction after the call, which is to be returned to after the called routine has finished.

return to zero signal /r t n təz ərəυ s n(ə)l/ noun a recording refer-

ence mark taken as the level of unmagnetised tape

reveal /r vi l/ verb to display previously hidden information once a condition has been met

reverb, reverberation noun a musical effect that gives the impression of depth in the sound

reverse /r v s/ verb to go or travel in the opposite direction

‘…the options are listed on the left side of the screen, with active options shown at the top left in reverse video’ [PC User]

reverse channel /r v s tʃ n(ə)l/ noun a low speed control data channel between a receiver and transmitter reverse characters /r v sk r ktəz/ plural noun characters which are displayed in the opposite way to other characters for emphasis

reverse engineering /r v s end'n ər ŋ/ noun a method of product design in which the finished item is analysed to determine how it should be constructed reverse index /r v s ndeks/ noun the movement of a printer head up half a line to print superscripts

reverse interrupt /r v s ntər pt/ noun a signal sent by a receiver to request the termination of transmissions reverse polarity /r v s pəυ l r ti/ noun a situation in an electric or electronic circuit in which the positive and negative terminals have been confused, resulting in the equipment not functioning

reverse Polish notation /r v spəυl ʃ nəυ te ʃ(ə)n/ noun mathematical

operations written in a logical way, so that the operator appears after the numbers to be acted upon, removing the need for brackets. Abbr RPN

reverse video /r v s v diəυ/ noun a screen display mode in which white and black are reversed and colours are complemented

revert command /r v t kə mɑ nd/ noun a command in text that returns a formatted page to its original state

revise /r va z/ verb to update or correct a version of a document or file

rewind / ri wa nd/ verb to return a tape or film or counter to its starting point

The tape rewinds onto the spool automatically.

RF, R/F noun the electromagnetic spectrum that lies between the frequency range 10KHz and 3000GHz. Full form radio frequency

RFC / ɑ ef si / noun a document that contains information about a proposed new standard and asks users to look at the

document and make any comments. Full form request for comment

RF shielding / ɑ ef ʃi ld ŋ/ noun thin metal foil wrapped around a cable that prevents the transmission of radio frequency interference signals Without RF shielding, the transmitted signal would be distorted by the interference.

RGB / ɑ d'i bi / noun a high-definition monitor system that uses three separate input signals controlling red, green and blue colour picture beams. Full form red, green, blue

COMMENT: There are three colour guns producing red, green and blue beams acting on groups of three phosphor dots at each pixel location.

RGB display / mɒn tə/, RGB monitor noun a monitor that uses RGB

ribbon cable / r bən ke b(ə)l/ noun

same as tape cable

rich e-mail / r tʃ i me l/ noun an e- mail that has a voice message attached to it rich text / r tʃ tekst/ noun text that includes formatting such as bold, italics, etc rich text format / r tʃ tekst fɔ m t/ noun a way of storing a document that includes all the commands that describe the page, type, font and formatting. Abbr RTF

RIFF /r f/ noun a multimedia data format jointly introduced by IBM and Microsoft that uses tags to identify parts of a multimedia file structure and allows the file to be exchanged between platforms. Full

form resource interchange file format

RIFF chunk / r f tʃ ŋk/ noun a chunk with the ID RIFF

RIFF file / r f fa l/ noun a file that contains tagged information that complies with the RIFF file format

right-click / ra t kl k/ verb to press and release the right-hand button of a computer mouse

right-click menu / ra t kl k menju / noun a small pop-up menu that appears when you click on the right-hand button of

a two-button mouse

right-hand button / ra t h ndb t(ə)n/ noun a button on the right-hand side of a two or three-button mouse right justification /ra t d' st fke ʃ(ə)n/ noun the process of aligning the text and spacing characters so that the right margin is straight

right justify /ra t d' st fa / verb to align the right margin so that the text is straight

right shift / ra t ʃ ft/ verb to move a section of data one bit to the right rightsizing / ra tsa z ŋ/ noun the process of moving a company’s information technology structure to the most cost-ef- fective hardware platform, which in practice often means moving from a main- frame-based network to a PC-based network

rigid disk / r d' d d sk/ noun a rigid magnetic disk that is able to store many times more data than a floppy disk, and usually cannot be removed from the disk drive

ring /r ŋ/ noun 1. a data list whose last entry points back to the first entry. chained list 2. the topology of a network in which the wiring sequentially connects one workstation to another

ring back system / r ŋ b k s stəm/ noun a remote computer system in which a user attempting to access it phones once, allows it to ring a number of times, disconnects, waits a moment, then redials

ringer equivalence number / r ŋərkw vələns n mbə/ noun full form of

REN

ring shift / r ŋ ʃ ft/ noun data movement to the left or right in a word. The bits falling outside the word boundary are discarded, and the free positions are filled with zeros.

ring topology / r ŋ tə pɒləd'i/ noun network architecture in which each computer or printer is connected together in a loop

ring topology network /r ŋ təpɒləd'i netw k/ noun a type of net-

work in which each terminal is connected one after the other in a circle

RIP abbr 1. raster image processor 2. routing information protocol

ripper / r pə/ noun a program that can be used to copy digital music from a compact disc onto a computer before converting it into a format in which it can be stored as a computer file

ripple-through carry / r p(ə)l θruk ri/ noun the fact that one operation produces a carry out from a sum and a carry in

ripple-through effect / r p(ə)l θrufekt/ noun (in a spreadsheet) the results, changes or errors appearing in a spreadsheet as a result of the value in one cell being changed

RISC / ɑ a es si / noun a CPU design whose instruction set contains a small number of simple fast-executing instructions, which makes program writing more complex but increases speed. Full form reduced instruction set computer.

WISC

Rivest, Shamir, Adleman / r vest ʃəm ə d(ə)lmən/ noun full form of RSA

(see)

RJ-11 / ɑ d'e lev(ə)n/ noun a connector with four connections, normally

used in telephone sockets in the USA

RJ-45 / ɑ d'e fɔ ti fa v/ noun a connector used in telephone systems with eight connections. A similar looking connector, often referred to as an RJ-45 connector is used to connect 10BaseT UTP cable in an Ethernet local area network.

RJE / ɑ d'e i / noun a batch processing system in which instructions are transmitted to the computer from a remote terminal. Full form remote job entry

RLE / ɑ el i / noun a data compression technique that stores any sequence of bits of data with the same value to a single val-

ue. Full form run-length encoding

RLL encoding / ɑ el el n kəυd ŋ/ noun a fast and efficient method of storing data onto a disk in which the changes in a run of data bits is stored. Full form runlength limited encoding

rm / ɑ em/ noun (in UNIX) a command to remove an empty subdirectory RMDIR abbr remove directory. Same as

RD

RO / ɑ əυ/ noun a computer terminal that can only accept and display data, not transmit. Full form receive only

roam /rəυm/ verb (in wireless communications) to move around freely and still be in contact with a wireless communications transmitter

robot / rəυ bɒt/ noun 1. a device that can be programmed to carry out certain manufacturing tasks which are similar to tasks carried out by people 2. same as bot2 robotics /rəυ bɒt ks/ noun the study of artificial intelligence, programming and building involved with robot construction robust /rəυ b st/ adjective referring to a system which can resume working after a

fault

robustness /rəυ b stnəs/ noun a system’s ability to continue functioning even with errors or faults during a program execution

rogue indicator /rəυ nd ke tə/ noun a special code used only for control applications, e.g. an end of file marker rogue value / rəυ v lju / noun an item in a list of data which shows that the list is terminated. Also called terminator role indicator /rəυl nd ke tə/ noun a symbol used to show the role of a index entry in its particular context

roll back / rəυl b k/ noun a function of a database application that stops a transaction and returns the database to its previous state

roll forward /rəυl fɔ wəd/ noun a function of a database application that allows the user to recover from an event such as a power cut by reading the transaction log and re-executing all the instructions to return the database to the state just before the event

roll in / rəυl n/ verb to transfer data from backing store into main memory roll out / rəυl aυt/ verb to save the contents of main memory onto backing store rollover / rəυləυvə/ noun a keyboard with a small temporary buffer so that it can still transmit correct data when several keys are pressed at once

roll scroll / rəυl skrəυl/ noun displayed text that moves up or down the computer screen one line at a time

ROM /rɒm/ abbr read only memory

Roman numerals / rəυmənnju mərəlz/ plural noun numbers repre-

sented using the symbols I, V, X, L, C, D and M

ROM BIOS /rɒm ba ɒs/ noun a code which makes up the BIOS routines stored in a ROM chip, normally executed automatically when the computer is switched on

ROM cartridge /rɒm kɑ tr d'/ noun software stored in a ROM mounted in a cartridge which can easily be plugged into a computer

romware / rɒmweə/ noun software which is stored in ROM

root /ru t/ noun 1. the starting node from which all paths branch in a data tree structure 2. a fractional power of a number root directory /ru t də rekt(ə)ri/ noun the topmost directory from which all other directories branch In DOS, the root directory on drive C: is called C:.

rot13 / rɒt θ ti n/ noun simple encoding that is used to scramble offensive messages posted in newsgroups

rotate /rəυ te t/ verb to move data within a storage location in a circular manner

rotate operation /rəυ te tɒpəre ʃ(ə)n/ noun same as bit rotation

rotating helical aperture scanner

/rəυ te t ŋ hel k(ə)l pətʃə sk nə/ noun a type of scanner in which the original image is lit and the reflection sent, through a lens and mirror, through a rotating spiral slit and finally onto a photodetector cell; as the spiral slit turns, it has the effect of moving up the image

rotation /rəυ te ʃ(ə)n/ noun the degree

to which an object has been rotated rough copy / r f kɒpi/ noun a draft of

a program which, it is expected, will have

changes made to it before it is complete round /raυnd/ verb to round down to

approximate a number to a slightly lower one of lower precision We can round down 2.651 to 2.65. to round off to approximate a number to a slightly larger or smaller one of lower precision Round off 23.456 to 23.46. to round up to approximate a number to a slightly larger one of lower precision We can round up 2.647

to 2.65.

round brackets / raυnd br k ts/ plu-

ral noun brackets in the form ( ) rounding / raυnd ŋ/ noun 1. an approx-

imation of a number to a slightly larger or smaller one of lower precision 2. the proc-

ess of giving graphics a smoother look

rounding error / raυnd ŋ erə/, round-off error / raυnd ɒf erə/ noun an

error in a result caused by rounding off the

number

round robin /raυnd rɒb n/ noun a way of organising the use of a computer by several users, who each use it for a time and then pass it on the next in turn

route /ru t/ noun the path taken by a message between a transmitter and receiver in a network The route taken was not the most direct since a lot of nodes were busy.

routed / ru t di / noun software that manages the routes taken by traffic across a network. Full form route-daemon. gated

router / ru t d/ noun 1. a communications device that receives data packets in a particular protocol and forwards them to their correct location via the most efficient

route 2. (in a LAN) a device that connect two or more LANs that use the same protocol and allows data to be transmitted between each network. The router works at the network-layer level of the OSI model.

bridge, OSI

routine /ru ti n/ noun a number of instructions that perform a particular task, but are not a complete program. They are included as part of a program. The routine copies the screen display onto a printer.

‘Hewlett-Packard has announced software which aims to reduce PC-network downtime and cut support costs by automating housekeeping routines such as issuing alerts about potential problems.’ [Computing]

COMMENT: Routines are usually called from a main program to perform a task. Control is then returned to the part of the main program from which the routine was called once that task is complete.

routing / ru t ŋ/ noun the process of determining a suitable route for a message through a network

routing information protocol

/ ru t ŋ nfəme ʃ(ə)n prəυtəkɒl/ noun a protocol used on the Internet to calculate the best route by which to transfer information over the Internet. RIP bases its selection on the distance that each route takes. Abbr RIP

routing overheads / raυt ŋ

əυvəhedz/ plural noun actions that have to be taken when routing messages The information transfer rate is very much less once all routing overheads have been accommodated.

routing page / raυt ŋ pe d'/ noun a videotext page describing the routes to other pages

routing table /raυt ŋ te b(ə)l/ noun a list of preferred choices for a route for a message stored within a router

row /raυ/ noun 1. a line of printed or displayed characters The figures are presented in rows, not in columns. 2. a horizontal line on a punched card Each entry is separated by a row of dots. 3. a horizontal set of data elements in an array or matrix

RPC / ɑ pi si / noun a method of communication between two programs running on two separate, but connected, computers. A software routine asks another computer on the network to process a problem and then displays the results. Full form remote procedure call

RPG abbr report program generator RS-232C noun an EIA approved standard used in serial data transmission, covering voltage and control signals

RS-422 noun an EIA approved standard that extends the RS-232’s 50ft limit RS-423 noun an EIA approved standard that extends the RS-232’s 50ft limit, introduced at the same time as the RS-422 standard, but less widely used

COMMENT: The RS232C has now been superseded by the RS423 and RS422 interface standards, which are similar to the RS232 but allow higher transmission rates.

RS-485 noun a standard that defines how serial devices are connected together for multipoint communications. This standard, approved by the EIA, supports higher rates of data transfer than the older RS232C standard and allows more connections to one line than the RS-422 standard. RSA noun a public-key cryptography system used to provide high-level of security (see) Full form Rivest, Shamir, Adleman. public key cipher system

RSI abbr repetitive strain injury RTDS abbr real-time data system RTE abbr real time execution RTF abbr rich text format

RTFM abbreviation a euphemistic abbreviation used in messages as an instruction to someone to ‘read the manual’

RTP abbr real time transport protocol

(see)

RTS abbr request to send signal

RTV / ɑ ti vi / noun real-time video compression used within DVI software to provide usable, but lower-quality, images that are compressed in real-time at 10 frames per second. Full form real-time

video

rubber banding / r bə b nd ŋ/ noun

elastic banding

rub out / r b aυt/ verb erase

rule /ru l/ noun 1. a set of conditions that describe a function The rule states that you wait for the clear signal before trans-

mitting. 2. in printing, a thin line rule-based system / ru l be st

s stəm/ noun software that applies the rules and knowledge defined by experts in a particular field to a user’s data to solve a problem

ruler / ru lə/ noun a bar displayed on screen that indicates a unit of measurement, often used in DTP or word-proces- sor software to help with layout

ruler line / ru lə la n/ noun same as tab rack

rules /ru lz/ noun a method of testing incoming messages for certain conditions, e.g. the name of the sender or the contents, and acting upon them

run /r n/ noun the execution by a computer of a set of instructions, programs or procedures The next invoice run will be on Friday. verb to operate, or to make a device operate The computer has been running ten hours a day.

run around /r n ə raυnd/ verb to fit text around an image on a printed page run in / r n n/ verb to operate a system at a lower capacity for a time in case of any faults

run on / r n ɒn/ verb to make text continue without a break The line can run on to the next without any space.

runaway / r nə we / noun an uncontrolled operation of a device or computer that occurs as a result of a malfunction or error

Run command / r n kə mɑ nd/ noun

(in Windows) a command that lets the user type in the name of a program that they want to run or a DOS command they want to execute

run-duration / r n djυ re ʃ(ə)n/ noun, adjective same as run-time

run indicator /r n nd ke tə/ noun an indicator bit or LED which shows that a computer is currently executing a program

run length encoding / r n leŋθ enkəυd ŋ/ noun full form of RLE

run-length limited encoding / r n leŋθ l m t d en kəυd ŋ/ noun full form

of RLL encoding

running head / r n ŋ hed/ noun the title line of each page in a document

run phase / r n fe z/ noun same as target phase

run-time, run duration noun 1. the period of a time that a program takes to run 2. the time during which a computer is executing a program also called run-dura- tion adjective referring to an operation carried out only when a program is running

run-time error / r n ta m erə/ noun a fault only detected when a program is run run-time library / r n ta m la brəri/ noun a library of routines that are only accessed by an application when it is running run-time licence / r n ta mla s(ə)ns/ noun a licence granted to a user to run an application

run-time system / r n ta m s stəm/ noun software that is required in main storage while a program is running, to execute instructions to peripherals, etc. run-time version / r n ta mv '(ə)n/ noun 1. a program code that has been compiled and is in a form that can be directly executed by the computer 2. a commercial interpreter program that is sold with an application developed in a high-level language that allows it to run

R/W abbr read/write

R/W cycle / ɑ d b(ə)l ju sa (ə)l/ noun a sequence of events used to retrieve or store data. Full form read/write cycle

R/W head / ɑ d b(ə)l ju hed/ noun an electromagnetic device that allows data to be read from or written to a storage medium. Full form read/write head

RX abbr receive The RXed signal needs to be amplified.

S100 bus, S-100 bus noun an IEEE696 standard bus, a popular 8– and 16-bit microcomputer bus using 100 lines and a 100-pin connector. bus (NOTE: say ‘S one hundred bus’)

SAA a trade name for a standard developed by IBM which defines the look and feel of an application regardless of the hardware platform. SAA defines which keystrokes carry out standard functions, the application’s display and how the application interacts with the operating system. Full form Systems Application Ar-

chitecture

safe format /se f fɔ m t/ noun a format operation that does not destroy the existing data and allows the data to be recovered in case the wrong disk was formatted safe mode / se f məυd/ noun a special operating mode of Windows 95 that is automatically selected if Windows 95 detects that there is a problem when starting safety margin / se fti mɑ d' n/ noun an extra amount of time or space provided so that errors can be absorbed

safety measures / se fti me'əz/ plural noun actions taken to make sure that something is safe

safety net / se fti net/ noun a software or hardware device that protects the system or files from excessive damage in the event of a system crash If there is a power failure, we have a safety net in the form of a UPS.

sag /s / noun a short drop in the voltage level from a power supply

salami technique /sə lɑ mi tek ni k/ noun computer fraud involving many separate small transactions that are difficult to detect and trace

SAM / es e em/ noun a type of storage in which a particular data item can only be accessed by reading through all the previous items in the list. Full form serial access memory

COMMENT: Magnetic tape is a form of SAM. You have to go through the whole tape to access one item, while disks provide random access to stored data.

sample / sɑ mpəl/ noun a measurement of a signal at a point in time The sample at three seconds showed an increase. verb to obtain a number of measurements of a signal which can be used to provide information about the signal

sample and hold circuit / sɑ mpəl ən həυld s k t/ noun a circuit that

freezes an analog input signal for long enough for an A/D converter to produce a stable output

sample interval / sɑ mpəl ntəv(ə)l/ noun a time period between two consecutive samples

sampler / sɑ mplə/ noun an electronic circuit that takes many samples of a signal and stores them for future analysis sample rate / sɑ mpəl re t/ noun a number of measurements of a signal that are recorded every second. A PC sound card normally supports one of the following three standard rates: 11,025, 22,050 and 44,100 samples per second, normally written as 11.025KHz, 22.05KHz and 44.1KHz.

sample size / sɑ mpəl sa z/ noun the size of the word used to measure the level of the signal when it is sampled sampling interval / sɑ mpl ŋ

ntəv(ə)l/ noun a time period between two consecutive samples

sampling rate / sɑ mpl ŋ re t/ noun a number of measurements of a signal recorded every second

SAR / es e ɑ / noun a register within the CPU that contains the address of the next location to be accessed. Full form store address register

SAS abbr single attachment station satellite / s tə la t/ noun a small system that is part of a larger system

COMMENT: In a network the floppy disk units are called ‘satellites’ and the hard disk unit the ‘server’. In a star network each satellite is linked individually to a central server.

satellite computer / s təla t kəmpju tə/ noun a computer doing various tasks under the control of another computer

satellite terminal / s təla tt m n(ə)l/ noun a computer terminal that is outside the main network saturated colour / s tʃəre t d k lə/ noun bright colours such as red and orange that do not reproduce well on video and can cause distortion or can spread over the screen

saturation / s tʃə re ʃ(ə)n/ noun a point where a material cannot be further magnetized

saturation noise / s tʃə re ʃ(ə)n nɔ z/ noun errors that occur as a result of saturation of a magnetic storage medium

saturation testing / s tʃə re ʃ(ə)ntest ŋ/ noun the process of testing a com-

munications network by transmitting large quantities of data and messages over it save /se v/ verb to store data or a program on an auxiliary storage device This WP saves the text every 15 minutes in case of a fault.

save area /se v eəriə/ noun a temporary storage area of main memory, used for registers and control data

save as / se v əz/ noun an option in an application that allows the user to save the current work in a file with a different name SBC / es bi si / noun a computer whose main components such as processor, input/output and memory are all contained on one PCB. Full form single board computer

SBM / es bi em/ noun an extension to the Red Book CD-Audio specification in which studio-quality 20-bit sound samples are stored in the 16-bit data format used by CD-Audio. Full form super bit mapping scalable / ske ləb(ə)l/ adjective 1. used to describe a computer, component or network that can be expanded to meet future needs 2. referring to fonts used for computer graphics that can be made to appear in a wide range of sizes

scalable software / ske ləb(ə)lsɒftweə/ noun a groupware application

that can easily accommodate more users on a network without the need for investment in new software

scalar / ske lə/ noun a variable that has

a single value assigned to it

scalar data / ske lə de tə/ noun a data type containing single values that are pre-

dictable and follow a sequence

scalar processor / ske lə prəυsesə/ noun a processor designed to operate at high-speed on scalar values

Scalar Processor Architecture

/ ske lə prəυsesə ɑ k tektʃə/ full form

of SPARC

scalar value / ske lə v lju / noun a

single value rather than a matrix or record scalar variable / ske lə veəriəb(ə)l/

noun a variable that can contain a single value rather than a complex data type such as an array or record

scale /ske l/ noun the ratio of two values

verb to scale down, scale up to lower or increase in proportion

scan /sk n/ noun an examination of an image or object or list of items to obtain data describing it The heat scan of the computer quickly showed which component was overheating. verb to examine and produce data from the shape or state of an object or drawing or file or list of items

The facsimile machine scans the picture and converts this to digital form before

transmission.

scan area /sk n eəriə/ noun a section

of an image read by a scanner

scan code / sk n kəυd/ noun a number transmitted from the keyboard to an IBM PC compatible computer to indicate that a key has been pressed and to

identify the key

scan conversion /sk n kən v ʃ(ə)n/ noun the process of converting an interlaced video signal to a non-interlaced signal or a composite to a separated RGB signal

ScanDisk / sk nd sk/ noun a utility that will check the hard disk for any problems and will try and correct problems that it finds

scan head / sk n hed/ noun a device used in scanners, photocopiers and fax machines, which uses photo-electric cells to turn an image into a pattern of pixels

This model uses a scan head that can dis-

tinguish 256 different colours.

scan length / sk n leŋθ/ noun the number of items in a file or list that are examined in a scan

scan line / sk n la n/ noun one of the horizontal lines of phosphor, or phosphor

dots, on the inside of a CRT or monitor. The monitor’s picture beam sweeps along each scan line to create the image on the screen.

scanner / sk nə/ noun a device that converts an image or document into graphical data which can be manipulated by a computer

‘Ricoh’s Fax 300L Computer Link is connected to a PC via a RS232C serial interface, and enables users to send faxes from within Dos and Windows applications without printing a hard copy: It can also act as a scanner for graphics, and a printer for documents.’ [Computing]

scanner memory / sk nə mem(ə)ri/ noun the memory area allocated to store images which have been scanned

scanning / sk n ŋ/ noun the action of examining and producing data from the shape of an object or drawing

COMMENT: A modem with auto-baud scanning can automatically sense which baud rate to operate on and switches automatically to that baud rate.

scanning error / sk n ŋ erə/ noun an error introduced while scanning an image scanning line / sk n ŋ la n/ noun a path traced on a CRT screen by the picture beam

scanning rate / sk n ŋ re t/ noun the time taken to scan one line of a CRT image scanning resolution / sk n ŋ rezəlu ʃ(ə)n/ noun the ability of a scanner to distinguish between small points. The usual resolution is 300 dpi.

scanning software / sk n ŋ

sɒf(t)weə/ noun a dedicated program that controls a scanner and allows certain operations, e.g. rotate, edit or store, to be performed on a scanned image

scanning speed / sk n ŋ spi d/ noun the speed at which a line or image is scanned

scan rate / sk n re t/ noun the number of times every second that the image on a CRT is redrawn

SCART connector / skɑ t kə nektə/ noun a special connector normally used to carry video or audio signals between video equipment

scatter-load / sk tə ləυd/ verb to load sequential data into various non-continu- ous locations in memory

scatter-read / sk tə ri d/ verb to access and read sequential data stored in various non-continuous locations

scavenging / sk v nd' ŋ/ noun the act of searching through and accessing database material without permission schedule / ʃedju l/ noun the order in which tasks are to be done, or the order in which CPU time will be allocated to processes in a multi-user system

Schedule+ / ʃedju l pl s/ noun a Microsoft Windows 95 software program that provides personal information management features, including a diary scheduled circuits / ʃed'u lds k tz/ noun telephone lines for data communications only

scheduler / ʃedju lə/ noun 1. a program that organises the use of a CPU or of peripherals which are shared by several users 2. utility software that helps users organise their meetings, appointments or the use of a resource

scheduling / ʃedju l ŋ/ noun a method of working that allows several users to share the use of a CPU

schema / ski mə/ noun a graphical description of a process or database structure schematic /ski m t k/ noun a diagram showing system components and how they are connected

scissor / s zə/ verb 1. to define an area of an image and then cut out this part of the image so it can then be pasted into another image 2. to define an area of an image and delete any information that is outside this area

scope /skəυp/ noun the range of values that a variable can contain

SCR abbr sequence control register scramble / skr mb(ə)l/ verb to code speech or data which is transmitted in such a way that it cannot be understood unless it is decoded

scrambler / skr mblə/ noun a device that codes a data stream into a pseudo-ran- dom form before transmission to eliminate any series of ones or zeros or alternate ones and zeros that would cause synchronisation problems at the receiver scrapbook / skr p bυk/ noun a utility on an Apple Macintosh that stores frequently used graphic images We store our logo in the scrapbook.

scratch /skr tʃ/ noun an area of memory or of a file used for the temporary storage of data verb to delete or move an area of memory to provide room for other data