Worlwide Trams Wiki:Namespaces

Like all wikis using the MediaWiki software, Worldwide Trams Wikia has twenty-two built-in namespaces: the main namespace, where page names have no prefix, and seventeen auxiliary types, each with its own prefix. In addition, there are two custom namespaces, with their own prefixes.
==Basic namespaces==
===Main===
The main namespace or article namespace is where the main content of the Wiki belongs (see Special:Allpages). It is the default namespace and does not use a prefix.
Example: National Tramway Museum.
=== (Project)===
The project namespace (prefix Worldwide Trams Wiki:, also called the Worldwide Trams Wiki namespace) is a namespace that provides information about Worldwide Trams Wiki and how to use it. You can use shortcuts for namespaces. The page you are now reading is located in the project namespace. (Possible issue with using worldwide trams wikia as the prefix. See 'confusing use…' on this page.)
The name of this namespace can instead be abbreviated to just WTW:, and there are many short redirects in the namespace written with capital letters that make pages easier to access.
Example: Worldwide Trams Wiki:Workforce UK Trams.
===Portal===
The portal namespace (prefix Portal:) is for reader-oriented portals that help readers find and browse through articles related to a specific subject. It also may contain links to encourage readers to contribute to relevant Workforces (see, for example, Portal:UKTrams or Portal:European Trams). The portal namespace and its associated talk namespace are the two custom namespaces in Wikipedia (they are not supplied by default in MediaWiki software). 
Example: Portal:UKTrams.
===User===
The user namespace (prefix User:) is a namespace that provides pages for Worldwide Tram Wiki's users' personal presentations and auxiliary pages for personal use, for example containing bookmarks to favorite pages. If you see in the Special:Recentchanges list that the user named "Bluegoblin7" has updated some pages, this user name is a link not to Bluegoblin7 but to User:Bluegoblin7.
Example: User:Bluegoblin7.
===Image===
The image namespace (prefix Image:, also called image description pages) is a namespace that provides info about images and sound clips, one page for each, with a link to the image or sound clip itself. See Special:Imagelist. There are three versions of links to images and sound files:
#[[Image:Foobar.jpg]] will insert the image directly into the page (not for sound files)
#[[Media:Foobar.jpg]] will make a text link directly to the image or sound clip
#[[:Image:Foobar.jpg]] will make a text link to the image description page
Example: :Image:Example.jpg.
===MediaWiki===
The MediaWiki namespace (prefix MediaWiki:) is a namespace containing interface texts such as link labels and messages. They are used for adjusting the localisation (i.e. local version) of interface messages without waiting for a new LanguageXx.php file to get installed. Each label and message has a separate page. Pages in this namespace are protected by default.
Example: Mediawiki:Help.
=== Template ===
The Template namespace was formerly a part of the MediaWiki namespace. It is used to define a standard text or boxes such as infoboxes and navigation boxes. Such "templates" can then be added to pages, either a copy of the text itself at the time of adding (substitution), or as a reference (kind of a link) to the text at the time of viewing the page (transclusion). When using transclusion any change made in the template immediately changes how the template looks in all the pages that use the template.
A collection of ready made templates are listed at Project:Template messages and Project:Navigational templates. 
Example: Template:POV.
For how to detect and use namespaces from within templates, see section Template programming below.
===Category===
The Category namespace contains categories of pages, with each displaying a list of pages in that category and optional additional text.
Example: :Category:4th century books.
===Help===
The Help namespace contains Help pages previously in the Wikipedia namespace, and at Meta. Several of these pages, in particular the ones copied from Meta, document the basic, technical features of Wikipedia.
Example: Help:Link.
==Talk namespaces==
Except for special pages, each namespace has an associated talk namespace. The talk namespaces are designated by adding talk: to the normal prefix. For example, the talk namespace associated with the main article namespace has the prefix Talk:, while the talk namespace associated with the user namespace has the prefix User talk:. Most of the pages in the talk namespaces are used to discuss changes to the corresponding page in the associated namespace. Pages in the user talk namespace are used to leave messages for a particular user. The user talk namespace is special in that, whenever a user's talk page is edited, that user (if logged-in) will see a box saying "You have new messages" on the top every page that they view until they visit their talk page. (Minor edits made by bots no longer set off the new message bar.)
Note that WT: expands to Wikipedia talk: when used at the beginning of a page name, in the same way as WP: expands to Wikipedia:. Example: [[WT:Verifiability]] links to Wikipedia talk:Verifiability
==Virtual namespaces==
There are two virtual namespaces that do not relate to pages stored in the database:Special and media.
The Special: namespace consists of pages (called special pages) that are created by the software on demand, such as Special:Recentchanges. These pages can be linked as usual, like [[Special:Recentchanges]], except when they have parameters; then, the full URL must be given, like an external link. For example, /w/wiki.phtml?title=Special:Recentchanges&days=3&limit=10, which returns the last ten changes.
A redirect to a Special page is not recommended because of its complications.
The Media: namespace can be used to link directly to an image or sound clip, rather than to the image description page. See information above on the image: namespace.
==Pseudo-namespaces==
=== Shortcut prefixes ===
Examples include:
; CAT
The CAT: pseudo-namespace provides shortcuts for pages in the Category namespace.
; MOS
The MOS: pseudo-namespace provides shortcuts for pages in the Wikipedia namespace related to the Manual of Style.
; P
The P: pseudo-namespace provides shortcuts for pages in the Portal namespace.
=== Transwiki ===
Transwiki: is a cross-project pseudo-namespace used for temporarily storing articles which need to be moved from one Wikimedia project to another. See transwiki in the Meta-Wiki for a full explanation.
== InterWiki links ==
Inter-language or inter-wiki prefixes don't define namespaces, they point to (pages in) other Wikimedia projects, outside the en.wikipedia.org website. They are mentioned here while they use a namespace-like prefix technique for linking. By default, that is unless combined with another in-project namespace prefix, they link to the main namespace of the related project. Examples of such prefixes include:
MW - for MediaWiki (mw:)
Wikt - for Wiktionary (wikt:)
For example, m:Meta:Babel and meta:meta:Babel both link to the "Babel" page in the project namespace (second prefix) of the Meta-Wiki project (first prefix). Another example: wikt:fr:Discuter:pied/fusion daf links to the "pied/fusion daf" page in the talk namespace (3rd prefix) of French (2nd prefix) Wiktionary (1st prefix).
==Non-standard namespaces==
Talk:Wikipedia:Namespace is an example of a non-standard (and not recommended) talk page name.
The Image:Image: namespace was never standard, and is no longer functional as of MediaWiki 1.3.
==Enumeration==
The (2 +) 16 + 6 2 namespaces in Wikipedia are shown here along with the variables that refer to them:
Namespace variable	Result (namespace name)
{{ns:-2}} 	
{{ns:-1}} 	
{{ns:0}} 	(main namespace, for regular Wikipedia articles, returns empty string)
{{ns:1}} 	(discussion pages for regular Wikipedia articles)
{{ns:2}} 	
{{ns:3}} 	
{{ns:4}} 	
{{ns:5}} 	
{{ns:6}} 	
{{ns:7}} 	
{{ns:8}} 	
{{ns:9}} 	
{{ns:10}} 	
{{ns:11}} 	
{{ns:12}} 	
{{ns:13}} 	
{{ns:14}} 	
{{ns:15}} 	
{{ns:100}} 	
{{ns:101}} 	
{{ns:102}} 	(WikiProject) currently pseudo-namespace (use discouraged)
{{ns:103}} 	(WikiProject talk) currently pseudo-namespace (use discouraged)
{{ns:104}} 	(Reference) currently pseudo-namespace (use discouraged)
{{ns:105}} 	(Reference talk) currently pseudo-namespace (use discouraged)
{{ns:106}} 	(See Wikipedia:Table: namespace and editor and bugzilla:2194) (currently changed back to pseudo-namespace)
{{ns:107}} 	(See Wikipedia:Table: namespace and editor and bugzilla:2194) (currently changed back to pseudo-namespace)
All namespaces with a positive number or zero in this list are searchable. Specifically, the and namespaces are not searchable.
== Template programming ==
Templates can automatically detect namespaces and for instance change how they look depending on what type of page they are used on. They can do this by using magic words such as {{NAMESPACE}} and parser functions such as {{#ifeq:}}.
Wikipedia has several meta-templates that make it easy to detect namespaces. Then you don't have to handle magic words and parser functions in your own template code. Or you can use them as code examples to learn how to do it. Here are two of them:
* – A very easy to use one. There are several variants of this one for different needs.
* – The extremely versatile one.
== See also ==
* Help:Interwiki linking, to link to other Wikimedia projects.
* Help:Namespace