XPath in content repositories also defines a small number of functions and one syntactic addition (the order-by clause). Content repository-related functions are prefixed with jcr:.
Note that the function signatures below are expressed in XPath terminology. In particular, the reference to the type element() means an XML element, which corresponds to a repository node. Similarly, the type attribute() refers to an XML attribute, which corresponds to a repository property and node() refers to an XML node which corresponds to a repository item (that is, a repository node or property).