What is a cookie
A cookie is a file containing an identifier (a string of letters and numbers) that is sent by a web server to a web browser and is stored by the browser. The identifier is then sent back to the server each time the browser requests a page from the server.
Cookies may be either "persistent" cookies or "session" cookies: a persistent cookie will be stored by a web browser and will remain valid until its set expiry date, unless deleted by the user before the expiry date; a session cookie, on the other hand, will expire at the end of the user session, when the web browser is closed.
None of the cookies we use contain any information that personally identifies a user.
Cookies can be used by web servers to identify and track users as they navigate different pages on a website and identify users returning to a website.
Delete and block cookies
Most browsers allow you to refuse to accept cookies; for example:
- In Internet Explorer you can block cookies using the cookie handling override settings available by clicking "Tools", "Internet Options", "Privacy" and then "Advanced".
- In Firefox you can block all cookies by clicking "Tools", "Options", "Privacy", selecting "Use custom settings for history" from the drop-down menu, and unticking "Accept cookies from sites".
- In Chrome , you can block all cookies by accessing the "Customise and control" menu, and clicking "Settings", "Show advanced settings" and "Content settings", and then selecting "Block sites from setting any data" under the "Cookies" heading.
Blocking all cookies will have a negative impact upon the usability of many websites.
You can delete cookies already stored on your computer; for example:
- In Internet Explorer, you must manually delete cookie files (you can find instructions for doing so at http://windows.microsoft.com/en-gb/internet-explorer/delete-manage-cookies#ie=ie-11).
- In Firefox, you can delete cookies by clicking "Tools", "Options" and "Privacy", then selecting "Use custom settings for history" from the drop-down menu, clicking "Show Cookies", and then clicking "Remove All Cookies".
- In Chrome, you can delete all cookies by accessing the "Customise and control" menu, and clicking "Settings", "Show advanced settings" and "Clear browsing data", and then selecting "Cookies and other site and plug-in data" before clicking "Clear browsing data".
Deleting cookies will have a negative impact on the usability of many websites.