Advanced deep linking

hey everyone!
ive got a realy cool site that uses deep linking to allow the user to use the back and forward buttons of their brower, as well as being directed to a certain page on the flash site without having to start at the homepage and navigate your way there.
DrawingArt.com is a site that uses this capability.

what confuses me is how you can go from page to page on their site, and the url updates itself, telling you what page you are one, and this is done without having to reload the entire page and downlaod the swf again. Ontop of that, if you look at the url’s of different pages carefully, i dont know how the site reads variables from the url because they are not defined. like when defining variables in the url with php, you write:
php?page=home_page

if anyone knows, i would like to know how drawignart.org uses its deep linking system.

thanks alot! :thumb: