Many XML applications have recommended prefixes.
For example, SVG elements often use the prefix svg and
Resource Description Framework (RDF) elements often have the prefix
rdf. However, these prefixes are simply conventions,
and can be changed based on necessity, convenience, or whim.
Before a prefix can be used, it must be bound to a URI.
These URIs are standardized, not the prefixes.
The prefix can change as long as the URI stays the same.