XSL (Extensible Stylesheet Language) is a language for expressing stylesheets for XML documents. It consists of two parts: a language for transforming XML documents, and an XML vocabulary for specifying formatting semantics. The originality and power of XSL is to be more general than just describing how XML documents should be presented and to allow as well to describe how these documents can be transformed into other documents. The part of XSL dealing with document transformation is called XSLT. The part of XSL dealing with formatting objects is called XSL-FO. XSL and XSLT are currently the object of working drafts at the W3C.