Yah, that's really all HTML... although there is some CSS in it too for part of it. HTML is all presentation layer. What people often fail to understand about the XSS cheat sheet is that they think it's about JavaScript. It's not. It's about HTML used to get JS on a page (there are a few exceptions like straight JS injection or header splitting, etc... but for the most part it's all HTML injection that causes JS to run). The Cheat Sheet is pretty complicated, and lots of it is only useful in very particular situations, so I don't blame you for feeling a little intimidated. But trust me, you can figure it out, it's not rocket science.
XSS isn't a language at all, it's just an HTML fragment that gets outputted by the server side code (in most cases). That's the easiest way to think of it. One of the obvious exceptions is stuff like anchor tags url/file/path/to/function.php#exploit-goes-here where it doesn't even get sent to the server, but JavaScript that runs client side does something unsafe with the anchor tag that causes code to run that the attacker controls.
- RSnake
Gotta love it.
http://ha.ckers.org