For a little while I was interested in Macromedia Flex, a presentation-level framework for "rich internet applicatiions". It isn't terribly hard to code in, but the apps you make can be a paiin to deploy if you don't use Flex Builder, a Dreamweaver like IDE. I installed it one Windows XP Pro and it went flawleesly, I even did it without admin priveleges. You can make some pretty nifty things that HTML, CSS and JavaScript just can't do. It's nice to experiment in, but if you aren't a big company or have your own server and lots of money, don't get it.

i dont relli understand what it means so do u mind pmming me and telling me what it is in more detail

It's similar to HTML. You type out an XML-like file, and upload it to your server. The differences: you need a server with Flex installed; the source code is compiled into a Macromedia Flash file, and the server makes a page that loads that Flash file; you need to make a whole bunch of configuration files to use your Flex "application"; and in general, it's expensive and designed for large companies who have their own servers.

Bottom line: So much to learn, so much to pay, the average web developer or website administrator won't like it. If you want to try it, download he installer from Macromedia's website, and install it (you don't need admin access on Windows 2000/XP). Otherwise, forget it exists.