A cookie is a very small encrypted text file that can be placed by a website in a computer or any other internet enabled device when that website is visited. It contains a unique reference number, the purpose of which to enable the website operator and, if different, the owner of the cookie, to know when an internet user has visited the website concerned; to keep track of that person when they are on the website; and, in some cases, to enable visits to and from other sites to be tracked. It is essentially an identification tag for an individual computer or other internet enabled device.
Broadly speaking there are two types of cookie (1) “session” cookies, which are stored temporarily in a computer’s memory and are automatically erased when you close your web browser: and (2) “persistent” cookies, which are stored the hard drive of a computer and which exist for longer, in some cases for years.
Some session cookies are essential to make a website operate properly, for example to allow visitors to switch between webpages or to complete a purchase on line without interruption.
Depending on its lifespan, a persistent cookie can be used to record an internet user’s login details and browsing preferences for a particular website so these features do not need to be reset each time that person visits that website. A persistent cookie may also be used to record how an internet user behaves on a website by recording which pages they visited, how much time they spent on each one, and if there is any other kind of interaction with the site what form this took. Such data can be used to improve the performance of a website.
Cookies may be classified as either first party or third party. A first party cookie is one which is set by or on behalf of a website operator. A third party cookie is one that is by set someone else, normally with the permission of the website operator.
There is a subset of cookies called “flash cookies” that may be set on a computer by websites that contain Adobe Flash media such as videos. These cookies can be used like ordinary cookies. They can also be used to back up such cookies. It is important to note that, unlike ordinary cookies, flash cookies cannot be controlled directly from your computer.
For more information about cookies in general, including how you may delete them or restrict their use on your computer, please visit http://www.aboutcookies.org. For information on how you can delete or restrict the use of cookies on your mobile phone please refer to the owner’s manual for your phone.
For specific information about how to delete or restrict flash cookies in relation to individual websites, please visit www.adobe.com/products/flashplayer/security. Please be aware that disabling the use of flash cookies may mean that you cannot see certain videos and flash based images on a website.