Recommendation

Date: Nov. 16, 1999
Link: http://www.w3.org/TR/xpath
Source Author or Organization: W3C

The XPath Recommendation is a joint work representing the combined efforts of the XSL Working Group and the XML Linking Working Group. XPath was created in order to provide a common syntax and semantics for querying and addressing the contents of XML documents that could be used by XSLT (XSL Transformation Language), XLink, and XPointer.

XPath gets its name through its use of a path notation as in URLs for navigating through the hierarchical structure of an XML document. XPath operates on the abstract, logical structure of an XML document as a tree of nodes.

XPath uses "expressions" that are evaluated into one of four basic datatypes with respect to a certain "context". The way that a context is determined differs for XSLT and XPointer. Both XSLT and XPointer extend XPaths "core functions", which are defined by its Core Function Library.