A document written in XSLT, referred to as a stylesheet, describes the transformation of a particular type of XML document into another format. These other formats can include not only XML languages, such as HTML and Scalable Vector Graphics (SVG), but languages using other syntaxes, such as plain text, Comma Separated Values (CSV), and any number of others—including your choice of proprietary formats. In fact, the range of output formats is limited only by the amount of work you want to do to create the appropriate stylesheet—or to locate an appropriate stylesheet created by a third party.

XSLT can be thought of as a little language, providing complete functionality for a limited set of tasks. A little language is defined as a specialized, concise notation, designed for a specific family of problems. Much simpler than a general-purpose programming language, a little program does a limited number of things very efficiently.

Although it was designed simply to provide for the transformation of XML documents, XSLT is often used to process XML documents in other ways. XSLT can be used to generate summary statistics about XML documents, store information from an XML file in a database, or communicate data from an XML file to a mobile device. Again, the applications are limited only by your imagination.