Stands for "Extensible Style Sheet Language Transformation." While XML is supposed to be a standardized language, not all XML documents use the same type of formatting. Therefore, the documents sometimes need to be "transformed," or modified so that another script or program will be able to read them. XSLT make this transition possible.
An XSLT style sheet provides a template with rules that XML documents must conform to. It receives an XML document as input and outputs a file that is recognizable by the intended program. For example, an XSLT may take a XML document that contains the technical specifications of a computer and turn it into an HTML page that can be displayed in a Web browser. Another XSLT may turn a XML document containing new stories and turn it into a printer-friendly text document.
XSLTs can be used to transform XML documents into a modified XML file or a completely separate format, such as the HTML and text examples above. In fact, by using XSLT style sheets, it is possible to output the same XML document on the Web, in a database program, in an e-mail message, or in a printed document. Also, because XML uses standard formatting based on tags, a single XSLT can be effective on a large range of XML-formatted files.