what are layers in web design?

[bball_1523]

I've noticed that some websites use layers... through dreamweaver as well.

--What are layers? What are they for? and why should anyone use them?

[mairving]

Layers can be done several ways, using javascript (http://www.conxiondesigns.com/tutorials/hideshow/index.php), using divs (http://hotwired.lycos.com/webmonkey/98/27/index3a_page2.html?tw=authoring) and using iframes (http://www.insidedhtml.com/tips/contents/ts10/page1.asp). Divs and Js are the best supported. You can also use a sort of layer by using CSS to create table backgrounds.

[Fuze]

But I'm wondering as well as he is, what exactly does a div do? What would you need a div for? And, is there an example I can see of them. I bought a copy of goLive awhile back and it had it in there, wasn't sure what it was for though.

[mairving]

Explanation of Div (http://www.htmlhelp.com/reference/html40/block/div.html)

example of div layers (http://www.insidedhtml.com/tips/contents/ts06/page1.asp) Click the demo link at the bottom.

Basically Div just allows for positioning of various elements on a page. They can be overlapping or not. Support is pretty good in most newer browsers, much better than iframes.