Cookies can be a good method for passing data between pages and especially for retaining data between sessions. Today, it's pretty safe to assume that anyone who is using your site can use cookies, since nearly every site that is non-static makes use of them(including all ASP sites that use sessions). It is also possible to set and read cookies using client-side code, but it is a bit more difficult. Reading and writing cookies using Active Server Pages' built in Request and Response objects is incredibly easy.