Not everything has a namespace

Sometimes a name is only a name

XML 1.0 didn't include namespaces, and neither do a lot of people... Because namespaces are a late and optional arrival, there are many vocabularies for which there is no namespace.
Documents without namespaces The Namespaces in XML Recommendation does not require that all XML documents use namespaces. Applications need to use other mechanisms, like prearrangement, DOCTYPE declarations, and vocabulary sniffing to determine what kind of document they have.
Identifying no namespace The default namespace may be declared to have no value, identifying that no namespace is associated with non-prefixed elements:
```
<nothingness xmlns="" />
```
Avoid using colons in names If your XML documents don't use namespaces, don't use colons in names. XML 1.0, second edition, makes this restriction explicit.