What is the relationship between XML namespaces and the XML 1.0 recommendation?
Although the XML 1.0 recommendation anticipated the need for XML namespaces by noting that element type and attribute names should not include colons, it did not actually support XML namespaces. Thus, XML namespaces are layered on top of XML 1.0. In particular, any XML document that uses XML namespaces is a legal XML 1.0 document and can be interpreted as such in the absence of XML namespaces.