Help:Namespaces

The standard MediaWiki installation has sixteen namespaces which can contain user-generated content; there are also two special namespaces which contain pages created 'on the fly' by the MediaWiki software. The standard namespaces are organised in pairs, with each pair containing a 'subject namespace' and a 'discussion namespace'. The namespaces are numbered from zero such that all subject namespaces have even indices, and all talk namespaces have odd indices.

Namespace	Nr. of pages	Note
(main)	1,007	The main namespace (no prefix). Here the pages are called articles and they should be about Norsk Data related stuff. The "search" and the "random page" feature looks (by default) in the main namespace.
User	32	Registered users (list: Special:Listusers) have a user homepage and a such page should be about this user. The pages is used to present oneself, for project-related bookmarks, and for drafts, tests, and other working material.
User talk	23	This namespace is the talkspace associated with the User namespace. Pages in this namespace are mainly used to leave messages for particular users or inform them of discussions that may be of interest to them. To facilitate this, when a page User talk:UserName is edited, whenever the user 'UserName' loads a page, a notice is displayed at the top of the page informing them of the edit: You have [[User talk:UserName|MediaWiki:Newmessageslink]] (MediaWiki:Newmessagesdifflink). This notice continues to appear until the user loads their user talk page to read the message.
NDWiki	20	This namespace is for matters about NDWiki. All subprojects to NDWiki is also placed here.
NDWiki talk	3	This is a talk namespace that is normally used for discussions related to the associated content pages.
Help	16	Here are all the help pages for the users, including User's Guides.
File	1,138	Here are all the images and other uploaded files (list: Special:Imagelist).
MediaWiki	29	System messages (list: Special:Allmessages).
Template	52	All templates are placed here. The wikitext code {{name}} refers to and includes the page Template:name.
Category	212	The Category namespace contains categories (list: Special:Categories), dynamic lists of other pages. To facilitate this, linking directly to a category page does not output an inline link, but instead includes the page into the associated category page. So the code [[Category:Help pages]] causes a category link to appear at the bottom of the page (at the bottom in the box marked "Categories"). Clicking on that link takes you to the category page, where this page is visible in the category list. To create an inline link to a category page, you need to add a colon to the front of the namespace: [[:Category:Help pages]] produces Category:Help pages.
Special	-	Consists of "special pages" (list: Special:Specialpages), which are created by the software on demand, for example Special:Recentchanges.