There are two types of cookies – “regular” cookies and session cookies. Session cookies are deleted when you close your while ordinary cookies remains on your computer for a longer period of time.
How you can avoid cookies
If you do not accept cookies, your browser can be set to automatically deny the storage of cookies or to be informed every time a website asks to store a cookie. The browser can also delete previously stored cookies. See your browser’s help pages for more information. You can also delete cookies manually from your hard drive at any time. If you choose not to accept cookies some features are still used, but you can limit the functionality of certain websites, such as your personal settings.