A namespace is part of a corpus, consisting only of the titles or addresses, e.g. page names. Design of a namespace is the core problem in databases, where this is called data design or information design or the data dictionary.

The most familiar namespaces to most people are:

Each of the above is an extraordinary work of collaboration. There is profound expense and attention involved in namespaces and the naming conventions that keep them consistent both internally and externally:

Maintaining any namespace requires name discipline and constant attention to new needs and problems. An effort like Wikipedia involves thousands of troll-years of effort to constantly challenge, change, and refute naming decisions, and come to a neutral point of view at least on the namespace, if not on section names and the text.

Translation between W3 OWL and Microsoft .NET namespaces provides an adequate example of why exact name discipline is required.