In HTML, we know (and all the browsers know!) that the <a> element defines hyperlink. However, this is not how it work with XML. In XML documents, you can use whatever element name you want - therefore it is impossible for browsers to predict what hyperlink elements will be called in XML documents.

The solution for creating links in XML document was to put a marker on elements that should act as hyperlinks.

Below is a simple example of how to use XLink to create link in an XML documents:

To get access to the XLink attribute and features we must declare the XLink namespace at the top of the document.

The XLink namespace is the : "http://www.w3.org/1999/xlink".

The xlink:type and the xlink:href attributes in the <homepage> element define that the type and href attributes come from the xlink namespace.

The xlink:type="simple" create a simple, two-ended link (means "click from here to go there"). We will look at multi-ended links later.

In HTML, we can create hyperlinks that either points to an HTML page or to a bookmark inside an HTML page (using #).

Sometimes it is more useful to point to more specific contents. For example, let's say that we want to link to the third item in the particular list, or to the second sentence of the fifth paragraph. This is the easy one with XPointer.

If the hyperlink points to an XML documents, we can add an XPointer part after the URL in the xlink:href attribute, to navigate (with an XPath expression) to a specific place in the documents.

For example, in the example below we use XPointer to point to the fifth item in the list with a unique id of "rock":