At the present time (late 2002), XPointer is divided among four specifications: a "framework" which forms the basis for indentifying XML fragments (http://www.w3.org/TR/xptr-framework/), a positional element addressing scheme (http://www.w3.org/TR/xptr-element/), a scheme for namespaces (http://www.w3.org/TR/xptr-xmlns/, and a scheme for XPath-based addressing (http://www.w3.org/TR/xptr-xpointer/).
The XPointer language is designed to address structural aspects of XML, including text content and other information objects created as a result of parsing the document. Thus, it could be used to point to a section of a document highlighted by a user through a mouse drag action.
===== Positional Element Addressing =======
The element() scheme introduces positional addressing of child elements. This is similar to a simple XPath address, but subsequent steps can only be numbers representing the position of a descendant relative to its branch on the tree.
For instance, given the following fragment
<foobar id="foo"><bar/><baz><bom/></baz></foobar>
the XPointer to bom would be
element(foo/2/1)
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