Users of other wikis, such as Wikipedia, may have noticed that namespaces are much more widely used on UESP.
Unlike other wikis (which put most pages in the "Main" namespace), on UESP everything is categorized. All articles related to the game Skyrim are in the [[Skyrim:]] namespace, for example. This helps to organize the content of the site, in particular in cases where pages with the same name are needed for each separate game. Therefore, instead of having a single page named [[Altmer]] that has to provide information on Altmer relevant to every TES game, there are multiple pages (Morrowind:Altmer, Oblivion:Altmer), each describing game-specific information, and also a Lore:Altmer page which describes general (non-game-specific) information. Furthermore, searching is customized to take advantage of namespaces.
A complete list of UESPWiki namespaces is available at UESPWiki:Namespaces.
You will most commonly notice namespaces when creating a link to a page. If you wanted to create a link for the word "Altmer", you could simply type the word like this:
If you later come back and edit that page again, however, you will find that your simple link has been changed into something like:
What has happened is that the wiki software has added the necessary namespace information to your link. The second version is the correct form of the link, but the first version is an easy shortcut that saves editors some typing.
When you need to create links to pages in a different namespace you have to add the namespace to the link yourself. There are additional shortcuts you can use. The way to use these is to choose the appropriate two-letter abbreviation, AR, DF, BS, RG, MW, TR, BM, OB, SI, or SR and format the link like so:
This will automatically create a link to Oblivion:Altmer from anywhere on the site. To create a link with a different display text, simply provide an additional parameter:
Finally, if you want to have a display name that is the same as the name of the article, you can format it like this:
This will add "Altmer" as display name, so the link will display as Altmer (without the namespace). When you edit the page again, you will see the wiki software has automatically changed the link to:
Generally speaking, all links within a given namespace should if possible link to other pages within that namespace. Thus, in an Oblivion article about a character who is an Altmer, it would not be correct to link to the Lore:Altmer page. Rather, the link should point to the Oblivion:Altmer page. Exceptions are made for subjects which cover multiple games, such as general lore subjects which are found in the Lore namespace. Also, there may be times when an article about something in one game will reference a related article in another, such as Oblivion:M'aiq the Liar, which is about a character who also appeared in Morrowind. But by default, you should always keep links within the same namespace as the page they are on.
When creating a page, be sure to create it in the correct namespace. In particular, pages created in the main namespace will in general be immediately deleted (see the Deletion Policy). If you follow a link to a non-existent page, or for any other reason are about to create a new page, first check that the page does not already exist somewhere else on the site.