Help:Categories

Each of the pages in the Category namespace represents what we call a category, a grouping of related pages, and each page in the category namespace contains an index for the pages of its category. For example, this page belongs to "Category:Help". If you open the "Category:Help" page, you will see a link to this page there.

Linking
When a page belongs to one or more categories, these categories appear in a light-green box at the bottom of a page. Each category page contains two parts:
 * The top part is optional and may contain text that can be edited, like any other page,
 * The bottom part is an ever-present, automatically generated, alphabetical list of all pages in that category, in the form of links.

To assign a category to a page, simply add the link " Category:Category name" to the page's wikitext. The normal place to add it is at the bottom of all text.

In order to link to a category on a page with normal text and not categorize said page in that category, one must put a colon before the Category namespace tag.

Sort key
By default, a page is sorted within a category under the first letter of its full name including the namespace. Also, MediaWiki groups accented characters separately from their unaccented version, so pages starting by À, Á, Ä, will be listed under separate headings, instead of under heading A.

A sort key specifies under which letter heading, and wherein the category list, the page will appear. You can add a sort key by placing it inside the tag after a pipe character. For example, the tag below will add the page under the heading "S".

Sort

Sort keys are case-sensitive, and spaces and other characters are also valid. The order of the sections within a category follows the Unicode sort order. The sort key does not change the page title displayed in the category.

Creating a category page
Categories exist even if their page has not been created, but these categories are isolated from others and serve little purpose for organization or navigation.

A category is created by creating a page in the Category: namespace. A category page can be created the same way as other wiki pages (see Help:Create an article); just add " " before the page title.

To avoid extra work, try searching within Pikmin Fanon's other categories or ask another user before creating a new category. The list of all categories can be found in "" in the "" box of the sidebar.

Unlike other wiki pages, it is not possible to rename (move) a category. It is necessary to create a new category and change the     tag on every page. The new category will not have the older category's page history, which is undesirable if there are many revisions.

Hidden categories
The categories that a page is in are normally listed at the bottom of the page. A category can be hidden from this list by adding the magic word " " to the category page. Hidden categories are not hidden from category pages.

Users can choose to see hidden categories in a separate "" list, by checking "" in the "" section of Special:Preferences.

Hidden categories are automatically added to Category:. This category is specified in the system message MediaWiki:Hidden-category-category.

Hierarchy
Categories may belong to other categories in a hierarchy. Since category pages are much like any other page, a category tag may be added to the bottom of a category page.

It is a good idea to organize all categories into a hierarchy with a single top-level category. The category structure can take the form of a tree with separate branches, but more often will have a graph structure. Never create a new category page without putting it in a category of its own; there should be a contiguous chain of parent-child links between each category and the top-level category.

Redirects
Like normal wiki pages, category pages can be redirected to other normal or category pages. However, this is not recommended, as pages categorized in redirected categories do not get categorized in the target category.

Tracking
Certain syntax issues, such as a broken image link, or too many expensive parser functions, can cause a page to be added to a tracking category.

Categories via templates
Categories can be added to templates. For a category that appears on the template but not the pages that the template is used on, put the category inside  tags. For a category that appears on pages the template is used on but not the actual template, use  instead of.

HotCat
HotCat is a gadget, which can be enabled in your perferences, an easier way of modifying categories. HotCat can quickly add, change, or remove categories without modifying the categories manually via wikitext. A brief demonstration of HotCat