URN
From MgmtWiki
Full Title or Meme
Uniform Resource Name [URN] is the term for a specific type of URI intended to persistently identify a resource, i.e., an identifier that will never change no matter how often the resource moves, changes labels, changes owners, etc. URNs are intended to last forever.
Context
In order to ensure the global uniqueness of URN namespaces, their identifiers (NIDs) are required to be registered with the IANA. Registered namespaces may be "formal" or "informal".