Extensible Markup Language (XML) is a markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable.
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Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation (that is, the look and formatting) of a document written in a markup language.
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XPath (XML Path Language) is a language for selecting nodes from an XML document. In addition, XPath may be used to compute values (strings, numbers, or boolean values) from the content of an XML document.
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XSLT (Extensible Stylesheet Language Transformations) is a declarative, XML-based language used for the transformation of XML documents. The original document is not changed; rather, a new document is created based on the content of an existing one.
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