XSLT stands for XML Style Language Transformation. It's a technology for translating one XML document into another XML document, based on a set of rules. XSLT is the language used to specify those rules (or templates). A common case is when you have a plain, unformatted web page. In this case, XSLT is used to specify rules for translating the plain HTML page into an attractive page, with headers, footer, fonts and colors. In other words, XSLT is used to apply style to an unformatted document. Thus the S stands for style. The text file containing the transformation rules is typically called a stylesheet.