XSLT

Terms:

XSL stands for EXtensible Stylesheet Language.
XSLT stands for XSL Transformations

Styles;
CSS for HTML documents.
XSL for XML documents.

XSLT is a language for transforming XML documents into XHTML documents or to other XML documents.

XSL consists of three parts:

* XSLT - a language for transforming XML documents
* XPath - a language for navigating in XML documents
* XSL-FO - a language for formatting XML documents

A common way to describe the transformation process is to say that XSLT transforms an XML source-tree into an XML result-tree.

Source: http://www.w3schools.com/xsl/