Editing Namespace (section)

===Hierarchy{{anchor|hierarchical namespace}}===
A naming scheme that allows subdelegation of namespaces to third parties is a '''hierarchical namespace'''.

A hierarchy is recursive if the syntax for the namespace names is the same for each subdelegation. An example of a recursive hierarchy is the [[Domain name|Domain name system]].

An example of a non-recursive hierarchy are [[Uniform Resource Name]] representing an [[Internet Assigned Numbers Authority]] (IANA) number.

{| class=wikitable
|+ Hierarchical namespace breakdown for urn:isbn:978-3-16-148410-0, an identifier for the book The Logic of Scientific Discovery by Karl Popper, 10th edition.
|-
! Registry !! Registrar !! Example Identifier !! Namespace name !! Namespace
|-
| [[Uniform Resource Name]] (URN) || [[Internet Assigned Numbers Authority]] || urn:isbn:978-3-16-148410-0 || urn || [https://www.iana.org/assignments/urn-namespaces/urn-namespaces.xml Formal URN namespace]
|-
| [[Uniform resource name|Formal URN namespace]] || [[Internet Assigned Numbers Authority]] || urn:isbn:978-3-16-148410-0 || ISBN || [http://tools.ietf.org/html/rfc3187 International Standard Book Numbers as Uniform Resource Names]
|-
| [[International Article Number (EAN)]] || [[GS1]] || 978-3-16-148410-0 || 978 || [[List of GS1 country codes|Bookland]]
|-
| [[International Standard Book Number]] (ISBN) || [[International ISBN Agency]] || 3-16-148410-X || 3 || [[German-speaking countries]]
|-
| [[International Standard Book Number#Publisher code|German publisher code]] || [http://www.german-isbn.de/ Agentur für Buchmarktstandards] || {{ISBNT|3-16-148410-X}} || 16 || [[Mohr Siebeck]]
|}