A transient, memory-resident ""cookie"" may be invoked in certain cases. For example, on the CASSIDI site a cookie is required to remember your selections as you move from page to page and enable CASSIDI's functionality. If you register for a Research user account, a cookie will be invoked when you login to your user account. These cookies will disappear when your browser is closed. If you check the 'Stay logged in' option, the cookie will persist for a maximum of 2 weeks before another login is required. You are not required to register for a user account to use this site. 