Background image..One image file with mulitple images?

[Bengal313]

Okay I am trying learn some web design technique and for the life of me I can't figure out how they are doing this. This website (http://www.adventnet.com/) has this file

http://image.adventnet.com/adventnethomepageimages.gif


as it's background image. But the one .gif file has all the images needed for the site. Where can I find a tutorial to learn this technique. It's kinda cool. I'm thinking advanced CSS has something to do with it.

[Apostropartheid]

I'm thinking this has something to do with negative margins, which pull back the background image to display only the part needed

[GO ILLINI]

you specify a width and a height, then the background-position
http://www.w3schools.com/css/pr_background-position.asp
or do it all in 1 description:

background: url("images/bg_tabs2.gif") no-repeat 100% -35px;

the -35px moves the image 35 pixels up so you cant see the top 35px.

-Adam