[XHTML?] Automatically serving up documents with proper language
 

Okay, so how do you do this?
I mean, a few times I have browsed to a webpage and it somehow automatically detects that my environement is Dutch, so it hands me a Dutch page.
Is there some API for browsers that allow you to check the language setting of the browser or something? I've had it happen on IE and on FireFox.
I would love to read more about this stuff.

you can do it in pretty much any programming language, from javascript to php. its a browser information thing that can be accessed. whatever your browser is set for, the page can redirect you to the proper language.

You mean via the Accept-language header (I just found that through google)?
Is that the only way?
Aren't there also some ip-to-country tools out there, anyone have any experience with them?