Quote Originally Posted by hertshelp
Now, for a simple XML file to be displayed on a webpage, I need to use a style sheet language, such as CSS or XSL or XSLT. Now, I know what CSS is and what it can do, but how does it differ to XSL and XSLT?

XSLT can transform the document into a readable HTML/XHTML page?? But I thought only XHTML pages could integrate XML? And what is XSL without Transofmration? Just CSS?
I think you misunderstand XML. It would be good for you to look at this Wikipedia article about XML. It also will answer your questions about DTD.

CSS is stylesheets for HTML/XHTML only. It has nothing to do with XML. XSL styles XML.

In order to display XML, you must have a parser. HTML doesn't just parse it by itself.