Cookies are small text files that are placed on your computer's hard drive by your web browser when you visit any website. They allow information gathered on one web page to be stored until it is needed for use on another, allowing a website to provide you with a personalised experience and the website owner with statistics about how you use the website so that it can be improved.
Some cookies may last for a defined period of time, such as one day or until you close your browser. Others last indefinitely.
Your web browser should allow you to delete any you choose. It also should allow you to prevent or limit their use.
For general information about cookies visit here.