C

  • Cable

    Literally, a wire insulated with plastic that is used to transfer electricity or information. Also a type of television service that is transmitted via a physical cable into your television.

  • Cached/caching

    When your browser saves information from web pages to help them load more quickly next time you visit them.

  • Canvas

    Also known as Project Canvas: an attempt by several major broadcast (including the BBC) to create standard IPTV system.

  • Capped service

    When there is a limit on how much you can use a service: for example, how much data you can download in a given month, or how much time you can spend accessing a wireless service.

  • Captcha

    A system that attempts to stop spammers and bots by asking you to re-type letters and numbers shown in an image to prove that you are a real person.

  • Cc

    Stands for 'carbon copy', and is similar to the 'To' field in an email. Putting someone's email address in this field will send them a copy of the email.

  • CD

    Stands for 'Compact Disc' - a nearly ubiquitous form of data storage which can be accessed via a special drive on your computer, or an external CD player. These can contain any sort of information, but are primarily used for either music or personal data files.

  • CD-R

    Stands for 'Compact Disc - Recordable'. A type of CD that can be permanently filled with data (like music, videos and other files) on a home computer, then viewed by other people.

  • CD-Rom

    Stands for 'Compact Disc - Read Only Memory'. A non-writeable disc, usually containing computer software or games.

  • CD-RW

    Stands for 'Compact Disc - Re-Writable'. A CD which can be filled and re-filled with data several times by different computers.

  • CGI

    Also known as 'special effects', this stands for 'Computer-Generated Imagery' and means video footage created by computers instead of using video cameras.

  • Character

    One letter or symbol of text. For example, one single traditional text message can be a maximum of 160 characters in length.

  • Charges

    Bills/costs incurred from using a product.

  • Chat site

    A website that allows people to send each other messages in real-time, without having to download any instant messaging software to their computer.

  • Chip

    A small computer component which processes information.

  • Chrome

    An internet browser made by Google.

  • Clean/cleaned

    In computing, this means deleting or reorganising data.

  • Cloud Computing

    Where the data is stored and accessed by the internet ('clouds') instead of on your computer: this can include online storage and online applications.

  • Cloud-based storage

    When data you upload online is kept not on single servers but across lots of different ones at the same time. This means if one of the servers breaks, less data is lost as a whole.

  • CMYK

    Cyan, Magenta, Yellow, Key Black: a way of combining colours to produce a full spectrum of shades. Another commonly-used way of doing this using different colours is RGB.

  • CNET

    A news website which provides, amongst other things, reviews of computer-related products and services, as well as software downloads and technology stories.

  • Coaxial

    A multilayered cable which can supply telephone, internet and television services.

  • Codec

    A computer program which can encript and decrypt (as well as translate) data, often used in video conferencing and streaming videos.

  • Compression

    When a file is made smaller by removing some of the information/finer detail electronically. This is often done to video and image files.

  • Content

    Any significant information on the internet - for example, an article/blog post, a video, an image or an animation.

  • Cookies

    Small files automatically downloaded to your computer by websites, which can contain information about you and what you've done on that website for the website to view next time you go online.

  • CPU

    Central Processing Unit - the 'brain' of the computer. When people talk about the speed of a computer they are talking about the speed of the CPU.

  • Crash

    When your computer temporarily stops working. It may pause or 'freeze' up, or tell you to restart or quit.

  • Crawler

    Also known as a bot or robot: a computer program which runs through the internet collecting data, often for search engines.

  • Creative Commons

    An organisation which has released freely-available copyright licences, allowing people to say how they would like to share their work on the internet. These licences are designed to help people share their creative works more easily.

  • Cross-posting

    Posting the same message across multiple platforms/websites: e.g. posting a status-update across different social media platforms like Twitter, Facebook and LinkedIn at the same time.

  • Crumb trail

    A series of text links across the top of a page that show you where you are on a website.

  • CSS

    'Cascading Style Sheets' - a type of code which works behind the scenes on a website to tell the browser how a website should look, including text-formatting, background colours and more.

  • Cuil

    One of the largest (if not the most popular) search engines, which keeps data about 127 billion different web pages.

  • Cursor

    The flashing vertical line on the screen that shows you where you are and where the next character you type will appear.

  • Cut and paste

    Taking information from one place and putting it in another.

  • CVV2/CVC

    The last part of the code above the signature strip on modern credit and debit cards, which is often required by online shops to verify that the card is genuine.

  • Cybercafé

    Also known as an internet café - a real café you can go to to drink coffee and buy internet access for short periods of time.

  • Cyberspace

    A term often used to describe the internet/online environment, but which was originally invented to describe an as-yet non-existent wholly interactive virtual world.

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