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Jargon Buster



  1. C

    A programming language commonly used by professional software developers.

  2. CAB file

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

  3. Cable broadband

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

  4. 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.

  5. CAD

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

  6. Caddy

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

  7. Calibration

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

  8. 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.

  9. Capture device

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

  10. Category 5

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

  11. CCD

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

  12. CD burner

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 Now superseded by DVD burners.

  13. CD-R

    A CD disc that can be written to once.

  14. CD-Rom

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

  15. CD-RW

    A re-recordable CD disc.

  16. Celeron

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

  17. Cell

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

  18. Chat room

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

  19. 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.

  20. Chip

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

  21. Chipset

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

  22. 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.

  23. CIS

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

  24. Click

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

  25. Client

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

  26. Clip art

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

  27. Clipboard

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

  28. Clock speed

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

  29. Clone

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

  30. 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).

  31. 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.

  32. CMYK

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

  33. Coaxial

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

  34. Code

    A term used to refer to computer programming instructions.

  35. Codec

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

  36. Colour depth

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

  37. Colour picker

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

  38. 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.

  39. Command line

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

  40. Command prompt

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

  41. Compact Flash

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

  42. Compile

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

  43. Component video

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

  44. Composite video

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

  45. 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.

  46. Configure

    To change the settings of a program or computer.

  47. Contention ratio

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

  48. 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.

  49. 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.

  50. Control Panel

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

  51. Cookie

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

  52. 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.

  53. 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.

  54. 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.

  55. CPU

    Central Processing Unit. Another term for a computer processor.

  56. Crash

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

  57. Crossover cable

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

  58. CRT

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

  59. Cryptography

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

  60. CSV

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

  61. 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.

  62. 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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