qnames is intended for questions related to XML namespacing and scoping of namespace declarations.
qnames(qualified names) are composed of a prefix name and a local name. The prefix name is mapped to a schema URI which contains a definition of the local name. For example the qnames for fully qualified HTML elements is explicitly written as:
<html:html xmlns:html='http://www.w3.org/1999/xhtml'>
<html:head><html:title>Example</html:title></html:head>
<html:body>
<html:a href="http://www.example.com">Example URI</html:a>
</html:body>
</html:html>
When used solely in element and attribute names, all QNames are identified by the XML processor and can logically be replaced by the URI/local-name pair they identify.
XSLT processors use qnames to identify the namespace of values.
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