For example:
http://www.insight.atbhost.net/index.php

OK, the page above will be the index.php page. if I got to click a link in the menu bar then it will reload the page and ONLY the content will change (according to the file the link is linked to). And the webaddress will not change?
Will switches work? I plan to make a script which will allow admin users to create, delete and modify (change name etc) the links. And I want it so I don't have to reconfigure the script all the time to get new links to work.