PHP Sessions - Maintaining State

In your readings, you may have come across mention of PHP Sessions. Sessions are another mechanism, in addition to GET, POST, and COOKIE parameters that allow you to "maintain state", meaning to pass data from one page to another.

PHP provides a set of functions that allow you to create Session variables. These are variables that are stored on the server, and last for a limited amount of time. They are very similar to Cookies, and in fact PHP does use Cookies to perform some of the tasks involved with Sessions. But PHP hides the internals of how Sessions work, so all you need to do is set the Session variables, and PHP handles the rest.

Here are some pages that cover sessions, and explain how to write PHP code to deal with them:

http://php.about.com/od/advancedphp/ss/php_sessions.htm
http://www.tizag.com/phpT/phpsessions.php
http://www.htmlgoodies.com/beyond/php/article.php/3472581
http://us3.php.net/session