XSL, the XML Stylesheet Language, converts XML or HTML documents into formatted HTML pages. The source pages can focus on content while the stylesheet can concentrate on formatting.

You can also use XSL to convert from any XML file to another XML. In fact, since XSL uses an XML syntax, you could even use XSL to create an XSL file!

XSL can be used in a number of useful ways:

From the command line to precompile documents
In a servlet engine with XTP or XSL-Filtering
Called directly from an application for dynamic conversions