You do not normally need to logout from this service although in some circumstances you may wish to do so.
Logout and remove my cookie from this computer
The cookie is stored on your computer and records your user number (not any personal information such as your login name or password). The web site uses this information to retrieve your own personal profile each time you return to the site.
If you are using a shared computer you may wish to use this link to logout and delete the cookie from this computer. Cookies from other web sites will be unaffected by this operation.