Jargon Buster

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A

AAC

Advanced Audio Coding. A type of lossy compressed music file that’s more efficient than mp3 (better quality for same size file).

Access point

Links wireless network users to a wired network.

Address bar

An area of a web browser into which internet addresses can be typed. Pressing enter then directs the browser to that exact page. The address bar is sometimes confused with a search bar. Typing addresses into a search field will produce a list of websites that may or may not match what you are looking for.

ADF

Automatic Document Feeder. A device that feeds each page of an original document into a photocopier or scanner, one by one.

ADSL

Asymmetric Digital Subscriber Line. A technology that converts a standard phone line into a broadband internet connection.

ADSL2

A newer, faster type of ADSL broadband.

Adware

Software that displays adverts.

Aero

The technology that provides fancy window effects in Windows 7 and some versions of Vista.

AGP

Accelerated Graphics Port. A slot used to connect graphics cards in older computers.

AI

Artificial Intelligence. A computer program designed to mimic the behaviour of humans or animals.

AIFF

Audio Interchange File Format. A digital audio format often associated with Apple Mac computers.

Ajax

Asynchronous Javascript and XML. A technology that allows websites to fetch fresh information from the web without loading a new page.

Amoled

Active-matrix organic light-emitting diode. A type of flat-panel display technology where each pixel/sub-pixel is self illuminating, negating the need for a backlight like on LCDs. The technology allows for very thin displays, which are low power and – as each pixel can be turned off completely – have very high contrast. They’re commonly found in phones and cameras and will soon be the choice for TVs too.

Analogue

A signal whose value can be any point within set bounds, as opposed to a digital signal which is either on or off.

Android

An operating system for portable computers and mobile phones, developed by Google, based on the Linux system and freely available for anyone to use and tinker with.

Animated GIF

A type of image file format that can store multiple frames along with a time of when to show each frame. It can be used to create simple animations, often used online to add animation to a webpage.

Annotation

A comment on a document, rather like a note jotted down on a paper document.

Anti-virus

Software that protects against and removes computer viruses.

Aperture

An opening that controls the amount of light entering a camera lens.

API

Application Programming Interface. A system built into a program so that other programs can work with it.

App

A small program designed to run on a phone or handheld computer (short for application). Could be a game, utility or any other type of program.

Applet

A small program, often one that runs within a larger program to perform a specific task.

Application

A computer program that performs a specific task, such as Microsoft Word for creating documents.

Aspect ratio

A measurement of the shape of a display. Traditional computer screens are 4:3. Widescreen displays are 16:9 or 16:10.

ATRAC

Adaptive Transform Acoustic Coding. A type of music file used by some older Sony players.

Attachment

A computer file, such as a word-processing document, sent along with an email.

Audible

A company that sells downloadable audio books. Also used to describe the files it uses.

Audio book

A book read aloud and recorded on tape, CD or as a digital file.

Autocorrect

A technology that corrects words as you type them.

Autoplay

A Windows feature that allows a program to be automatically started when a disk is connected to a computer

Autosum

A tool in Excel that provides a quick total of the selected cells.

Autotrace

A tool in some photo editors that attempts to trace an image, converting it into vector graphics that can be resized.

AV

Audio/Visual. Anything to do with devices that can show/record video or play/record sound.

Avatar

A graphic or icon used to represent a computer user, either online or in a video game.

AVCHD

Advanced Video Coding High Definition. A standard for storing high-definition video. AVCHD discs can be played by most Blu-ray players.

AVI

Audio Video Interleave. A type of video file. AVI is known as a container format, as it can hold many types of audio and video.

AV Sender

A device that sends audio and video signals wirelessly.

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B

Backup

A second copy of valued files, kept in case the originals are damaged.

Back up

The process of making a copy of valued files in case the originals are damaged.

Banding

Unwanted stripes on a printed page or display.

Bandwidth

A measure of how much information can be transferred through a connection at one time.

Baud

A measure of data transfer speed. One baud indicates one signal sent per second.

Bayesian

A technique used by junk email filters to identify junk based on past experience.

BD-R

A write-once recordable Blu-ray disc format.

BD-RE

A rewriteable Blu-ray disc format.

BD-Rom

Blu-ray disc read-only memory. A type of optical disc that cannot have files added to it. Commonly used for distributing videos content and games.

Behavioural advertising

Online ads targeted at users based on their web usage or email history – people who frequent pet forums might see more ads for dog food, for instance.

Beta

A version of software that’s almost, but not yet finished. Beta versions are often released so they can be tested.

Bezel

The plastic or metal border that surrounds a computer or TV screen.

Binary

A system for counting and storing information as a series of ones and zeros.

Biometrics

Using measurable personal characteristics, such as fingerprints, for identification.

BIOS

Basic Input Output System. Essential software built into every PC which connects the vital components. It’s visible for a few seconds when the PC starts.

Bit

A contraction of ‘Binary Digit’, this is the smallest item of information a PC can handle. A bit can hold the value 1 or 0.

Bitmap

A type of image file made up from a grid of pixels. Bitmaps have a fixed size and cannot be resized without losing quality.

Bit rate

A measure of data transfer speed, or of the quality of digital video or audio files.

Bittorrent

A technology for downloading files. Allows even very large files to be downloaded quickly.

Blacklist

A list of files, email addresses or websites known to be bad.

Blanking plate

A piece of plastic fitted to a PC, and designed so it can be removed when adding a new part in its place.

Bleed

A printing term for the areas of an image or document that don’t fit on the printed page.

Blog

Short for Web Log, blogs are websites that contain individual entries; new entries are added at the top. Often used for diaries and news.

Bluetooth

A technology that allows devices to communicate wirelessly over short distances.

Blu-ray

A type of optical disc used to store high-definition films, or up to 50GB of files.

BMP

Bitmap. A type of image file.

Bookmark

A favourite site stored in the Firefox web browser. Internet Explorer bookmarks are called Favorites.

Boolean

Logical statements such as AND, IF and OR used in programming. Named after the mathematician George Boole.

Boot

The process of starting up a PC after it has been turned off.

Boot disk

When it starts the computer looks on one disk for instructions. This is normally the hard disk, but in case of problems other boot disks can be used.

Boot sector

The area on the hard disk where the computer looks for instructions on how to start Windows.

Botnet

A group of infected computers connected together via the internet, and used to infect other PCs, send junk email and perform other criminal tasks.

Broadband

A fast, permanently connected internet connection such as ADSL or cable internet.

Browser

Short for web browser. A program used to view and interact with websites.

Buffer

Memory fitted to a device so it can store any information that arrives more quickly than it can be processed.

Bug

A mistake in an application’s computer code that leads to unintentional or unexpected results.

Burn

To write data onto a CD, DVD or Blu-ray disc.

Byte

A measure of data. One byte is eight bits, or enough to hold one character. 1,024 bytes make a kilobyte (KB).

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C

A programming language commonly used by professional software developers.

CAB file

A ‘cabinet’ file that contains many smaller files, often used when distributing software and unpacked automatically.

Cable broadband

Broadband delivered via the UK’s cable TV network by companies such as Virgin Media. Requires a special cable modem.

Cache

A temporary space for storing information. Can be memory used on a computer processor, or space on a hard disk used by a web browser.

CAD

Computer Aided Design. Software used to create 3D models.

Caddy

A box into which you can fit a hard disk, converting it into an external drive.

Calibration

The process of checking and adjusting a piece of equipment. Printers often need to calibrate themselves before use.

Captcha

A tool used by websites to verify that you are human and not a spammer by asking you to type in some words or numbers.

Capture device

A peripheral used to capture analogue video and convert it into a video file on your computer.

Category 5

A name given to standard computer network cables. Sometimes shortened to Cat 5.

CCD

Charge-coupled device. A type of light sensor used in many cameras and scanners.

CD burner

An optical drive that can write to CD-R discs. Now superseded by DVD burners.

CD-R

A CD disc that can be written to once.

CD-Rom

A CD formatted so it can contain files to be read by a computer. Cannot be written to.

CD-RW

A re-recordable CD disc.

Celeron

A brand name used by Intel for low-cost processors.

Cell

Spreadsheet programs split up the page into many small areas known as cells. Each can be identified by its column and row.

Chat room

A place for people to chat online, either via a website or using special software.

Checksum

The result of a mathematical calculation made using a file. The checksum can be used to verify that a file’s contents have not been tampered with.

Chip

Short for microchip. Many microchips are used in each PC to perform various tasks.

Chipset

A group of microchips. Often used to refer to the chips used on a computer motherboard that link the processor with other components.

Chromakey

A video trick often known as bluescreen or greenscreen, where something is filmed in front of a coloured backdrop that is then replaced with another image.

CIS

Compact Image Sensor. A type of sensor used in smaller and cheaper scanners.

Click

To press down and then release a key or button. If no other details are given, use the left mouse button.

Client

On a computer network client computers are connected to and retrieve information from a server.

Clip art

A collection of drawings that can be inserted into documents or presentations.

Clipboard

Part of a computer’s memory. Text, images or other information can be copied to the clipboard and pasted elsewhere.

Clock speed

The speed at which a computer processor can perform operations. Measured in Gigahertz (GHz).

Clone

In image-editing software the clone tool allows you to copy one area and paint it over another.

Cloud computing

A generic term for software services and applications that are provided to the user via the internet, rather than being installed on a computer hard disk. Cloud applications are used in a web browser; examples include office applications (such as Zoho) and backup services (such as Trend Micro Safesync, and BT Digital Vault).

Cmos

Complementary metal-oxide semiconductor. Can refer to both a type of image sensor chip used in some digital cameras and another chip on computer motherboards that stores the date and time.

CMYK

Refers to the four coloured inks found in many printers: Cyan, Magenta, Yellow, and blacK.

Coaxial

A type of cable where one wire is surrounded by insulation, which is then surrounded by another wire.

Code

A term used to refer to computer programming instructions.

Codec

Short for Compressor/Decompressor. A file that tells a computer how to record or play a type of media file.

Colour depth

A measure of how many colours a computer can display. 24-bit colour, for example, allows for more than 16 million colours.

Colour picker

The equivalent of a colour palette in a computer paint program. It allows you to click the colour you want.

Command key

A key used on Apple computer keyboards next to the space bar. Sometimes known as the Apple key, but not always marked with an Apple logo.

Command line

A way to control a computer by typing instructions one at a time. In Windows this is called the command prompt.

Command prompt

A black window into which you can type instructions. To see it click Start, Run, type cmd and press Enter.

Compact Flash

A type of memory card used in high-end digital cameras and some older models. Often abbreviated to CF.

Compile

After software has been written it must be converted into a program that can be run. This process is called compilation.

Component video

A type of high-quality video connection that uses three cables, plus two more for sound. Can carry high-definition video.

Composite video

A low-quality type of video connection that uses one cable for video. Normally colour-coded yellow.

Compression

The process of reducing the size of a file or files by encoding the data inside them. ZIP files are an example of compression.

Configure

To change the settings of a program or computer.

Contention ratio

Refers to the maximum number of customers that at any one time can connect to an internet service provider’s equipment.

Context menu

A menu that displays options relevant to the area in which it is displayed. In Windows right-clicking often displays a context menu.

Contrast ratio

A measure of the difference between the darkest and lightest possible shades shown by a screen. Screens with higher contrast ratios are good for watching movies or playing games.

Control Panel

A tool in the Start menu that allows you to configure most aspects of how the computer and Windows will run.

Cookie

A small text file stored on your computer by a website. Used to store browsing preferences, website log-in details and so on.

Copy and paste

Copying information from one part of a document and pasting it elsewhere, either in the same file, another file or even in another program.

Core

Most modern processors are effectively multiple processors squeezed onto a single chip and work together to increase performance. These individual processors within a processor are called ‘cores’. The more cores a processor has, the faster it should be – for this reason single-core processors are rare. Dual-core and quad-core processors are the most common.

Coverage

Wireless and mobile phone networks have a limited range, so the areas in which they can be used – the coverage – is limited. Mobile phone networks often have poor coverage in rural areas.

CPU

Central Processing Unit. Another term for a computer processor.

Crash

What happens when a computer program goes awry and stops working. Some serious crashes can require you to restart the computer.

Crossover cable

A special network cable required when connecting two computers directly to one another.

CRT

Cathode-ray tube. The technology used in older, non-flat-screen televisions and computer displays.

Cryptography

The science of scrambling data so it can only be read with the required key or code word.

CSV

Comma Separated Value. A basic spreadsheet file format that all spreadsheet programs are expected to understand.

Cursor

Can refer to the mouse pointer on screen or a flashing shape on the screen that shows where the next letter you type will appear.

Cut

To move the selected text, file or area of an image to the clipboard, removing it from its previous position.

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C

DAAP

Digital Audio Access Protocol. A technology used by Apple’s iTunes software to send music across a network.

DAB

Digital Audio Broadcasting. The system used in the UK for digital radio.

Database

A file used to store information. Databases can contain one or more tables of data, plus functions used to process it.

Data breach

A term used for when confidential data is lost or stolen.

Data table

The table of information in a spreadsheet used to create a chart.

DDR

Double Data Rate. A type of computer memory, now largely superseded by DDR2 and DDR3.

DDR2

A type of computer memory, newer than DDR but older and slower than DDR3.

DDR3

The newest, fastest commonly used type of computer memory.

Dead pixel

Flat-screen monitors are split up into millions of coloured pixels. A pixel is ‘dead’ if it is always stuck on one colour.

Dead spot

A term used to describe areas where you cannot connect to a wireless network because the signal is impeded in some way.

Decoder

A device that takes the surround-sound information from a film and splits it into channels, one for each speaker. Decoders and amplifiers are often combined.

Decryption

The process of unscrambling encrypted data or files.

Dect

Digital Enhanced Cordless Telecommunications. A technology used by cordless digital home telephones.

Default

A standard setting used by a program or Windows itself unless you tell it otherwise.

Definition file

A file downloaded by an anti-virus program, giving it details of how to spot the latest threats.

Defragment

To reorganise the data stored on a hard disk so files are stored in one piece and can be accessed quickly. Sometimes shortened to defrag.

Denial of Service

To attack a website by overloading it with requests, preventing it from working properly.

Desktop

The background area of Windows where icons can be shown.

DHCP

Dynamic Host Configuration Protocol. A system where one device on a network, normally the router, distributes network addresses to the others on request.

DHTML

Dynamic HTML, an umbrella term for techniques used to make websites more interactive.

Dialogue box

A window that pops up to display or request information.

Dial-up

Connecting to the internet using a non-broadband modem and telephone line.

Dial-up Networking

The part of Windows that allows it to connect to the internet using a traditional modem and phone line.

Digital

Information transmitted or stored as a series of ones and zeros.

Digital audio output

A connection that allows a computer to output surround sound digitally so it can be processed by a decoder.

Digital signature

A block of scrambled data that can be used to verify the sender of an email.

Digital sound output

A way to get sound from a device such as a computer, into an amplifier, speakers or other computer. Offers higher quality than conventional sockets and can be used for surround sound.

Digital stabilisation

A technique that can attempt to remove blur from a photo or video by digitally processing the result. Not as effective as optical stabilisation.

Digital zoom

Gives the effect of zooming in by cropping the image from a camera, but unlike optical zoom this means detail is lost.

Dimm

Dual Inline Memory Module. An older standard for computer memory modules.

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Java

Javascript

Joystick

JPEG

Jumper

Justified

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