They are used to keep track of which products you have lying in your shopping cart or to the preferences you have set for a particular service or capture. Cookies are also used to serve ads that try to tune in to your needs and interests on the websites you visit. This way this site Works together with companies who make it possible to show you relevant ads on websites other than this one. These companies keep the accumulated interests up to six months, then this information is destroyed.
You can enable or disable the cookies that give advertisers and website owners an insight into your interests, in http://www.youronlinechoices.eu/uk/ at 'Your Ad Choices'. Here you can also specify which companies are, and which are not, allowed to record your surfing habits. You can organise this by one button click. The cookies that keep track of your passwords, logins and other preferences you can switch on or off via your browser settings.