A namespace is a collection of pages with similar purpose. It appears as a prefix to page names. The MediaWiki software has many default namespaces, and Yume Wiki uses them for the wikis it hosts.
Basic information on namespaces can be found on the MediaWiki help page.
Definition
The most basic part of a namespace is the name itself, which is the prefix the page has. Each namespace also has a number, which acts as a unique ID, and is always even. Adding 1 to the namespace number gives the number of the corresponding talk space, used for discussing the subject page. It has the same namespace except with talk appended.
For example: the current page's full name is Help:Namespaces. This is in the namespace Help which has the number 12. This page's corresponding talk page is titled Help talk:Namespaces. This is in the namespace Help talk, which has a number of 13.
Usage
Separating wikis into different namespaces creates a static and consistent way to identify pages. For example, Yume Nikki:Hell will not be confused with Dotflow:Hell. Another positive is having different styles when viewing pages using the default Cosmos skin and the Citizen skin.
Namespaces are most commonly used in wikilinks. For example, to link to a page on the Yume Nikki Wiki, the namespace must be prefixed to the page title, such as in [[Yume Nikki:Uboa|Uboa]].
Links to the File and Category namespaces must be prefixed with a colon :. For example, [[File:NoImage.png]] will embed the file directly into the page, but [[:File:NoImage.png]] will produce the link File:NoImage.png.
Namespaces are also seen prefixed to pages listed in categories. This can be useful when a category has pages from multiple namespaces (such as Category:Article Stubs), but is otherwise redundant. There is no way to hide them.
Notable namespaces
Some namespaces have special importance or function.
Main
The main namespace, also called the mainspace, is for the main articles of a wiki. In Yume Wiki, the mainspace was split off to the sister site, the Yume Nikki Fangames Wiki, which uses it for pages on fangames and fangame developers. The reason for the split is that they were orginally individual wikis, and merging them would introduce filename conflicts that cannot be easily resolved.
Special
The Special namespace is reserved for special pages, which have a unique function instead of holding content. This can be information about the wiki, lists of content for maintenance purposes, or tools that are helpful for finding and editing content.
List
The below tables list the namespaces of Yume Wiki in addition to some information about them. For the default and extension namespaces, the purpose of the namespace is described. For the wiki namespaces, it shows the shortened form used in URLs, and for most of them an abbreviated form that users have adopted.
