Editing Uniform Resource Name (section)

===Formal===
Approximately sixty formal URN namespace identifiers have been registered. These are namespaces where Internet users are expected to benefit from their publication,{{sfnp|RFC 8141|2017}} and are subject to several restrictions. They must:

* Not be an already-registered NID
* Not start with {{code|urn-}}
* Be more than two letters long
* Not start with {{code|XY-}}, where XY is any combination of two [[ASCII]] letters
* Not start with {{code|x-}} (see "Experimental namespaces", below)