Cookies are small text files which are downloaded to your computer or device when you visit a website or application. Your web browser (such as Internet Explorer, Mozilla Firefox or Google Chrome) then sends these cookies back to the website or application on each subsequent visit so that they can recognise you and remember things like personalised details or your user preferences.
Cookies are very useful and do lots of different jobs, helping to make your experience on websites as smooth as possible. For example, they let you move between web pages efficiently, remembering your preferences, and generally improving your experience. Where relevant, they might also help to ensure that adverts you see online are relevant to you and your interests. Cookies can be categorised as session or persistent cookies, depending on how long they are used for:
Session cookies - only last for the duration of your on-line session and disappear from your computer or device when you close your browser.
Persistent cookies - stay on your computer or device after the browser has been closed and last for the period of time specified by that cookie. These persistent cookies are read each time you visit the site that placed them.
Update: Evercookie Since 2010 it is virtually impossible to avoid or delete Evercookies from your computer; see: http://samy.pl/evercookie/This website does not use Evercookies.