Extensible Stylesheet Language is a family of components used to render XML code.
XSL: Extensible Stylesheet Language is a family of components used to render XML code. XSL uses a XML notation, CSS uses its own. XSL consists of a number of subsets that allow you to use a markup language, such as HTML or XHTML, to manage the presentation of the data contained within the XML document. XSL files state rules for verification and also convert the XML data into a readable Internet file. By using a style sheet, you develop a core XML file that holds data and then author the template for a page to display the data. Included in the XSL languages are XSLT, XPath, XPointer and XLink, just to name a few. All these components work together to produce a readable version of the XML data.
XSL uses the basic XML model for syntax and structure. If you understand XML, you can write a style sheet for it.
XSL is different from CSS: XSL uses a XML notation, CSS uses its own. In CSS, the formatting object tree is almost the same as the source tree, and inheritance of formatting properties is on the source tree. In XSL, the formatting object tree can be radically different from the source tree, and inheritance of formatting properties is on the formatting object tree.