- Uniform Resource Identifier (URL oder URN)
- Uniform Resource Location (Wo zu finden)
- Uniform Resource Number (eindeutiger Identifier)
<svg xmlns="http://www.w3.org/2000/svg">
<!-- ... -->
</svg>
- Attribute nicht implizit im default-NS!
<hr:svg xmlns:hr="http://www.w3.org/2000/svg">
<hr:g>
<!-- ... -->
</hr:g>
</hr:svg>
http://www.w3.org/1999/XSL/Transform
http://www.w3.org/1999/XSL/Format
http://www.w3.org/2001/XMLSchema
http://www.w3.org/2000/svg
http://www.w3.org/1999/02/22-rdf-syntax-ns
http://www.w3.org/2001/SMIL20
http://www.w3.org/2001/vxml
http://www.w3.org/1999/xlink
http://www.w3.org/2002/xforms
http://www.w3.org/1999/xhtml
http://www.w3.org/1998/Math/MathML