1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 2 <html xmlns="http://www.w3.org/1999/xhtml"> 3 <head> 4 <meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type" /> 5 <title>Cookies, Sessions, Users and Persistent Information</title> 6 <meta name="generator" 7 content="amaya 8.1a, see http://www.w3.org/Amaya/" /> 8 <link href="styles.css" rel="stylesheet" type="text/css" /> 9 </head> 10 <body> 11 <h1>Cookies, Sessions, Users and Persistent Information</h1> 12 <p>Due to the nature of the communications mechanisms 13 involved, Web applications do not have automatic or "magic" 14 knowledge about the people or entities accessing them as application 15 users. Moreover, Web applications do not necessarily remember anything 16 about what that user has done before. Due to this behaviour, where 17 every request must tell the application as much as possible for an 18 operation to be carried out, Web applications are referred to as being 19 "stateless".</p> 20 <p>Yet there are a number of ways of maintaining "state" information - 21 that is, to remember the following things:</p> 22 <ul> 23 <li>Some kind of identify for the user, if only to be able to say 24 that such a user has visited before (if not to actually give them a 25 name).</li> 26 <li>Some details about their previous interactions with the 27 application.</li> 28 </ul> 29 <p>Such state information is typically provided using a number of 30 different mechanisms:</p> 31 <ul> 32 <li><a href="cookies.html">Cookies</a></li> 33 <li><a href="sessions.html">Sessions and Persistent Information</a></li> 34 <li><a href="users.html">Users and Authentication</a></li> 35 </ul> 36 </body> 37 </html>