Help/Categories
Categories provide automatic indexes. You can categorize pages and files by adding one or more Category tags to the content text. These tags create links at the bottom/right of the page that take you to the list of all pages in that category, which makes it easy to browse related articles.
Summary
Each of the pages in the Category namespace represents a so-called category, a grouping of related pages, and contains an index for the pages of its category. For example, this page belongs to "Category:Help". If you open the category page, you will see a link to this page there.
When a page belongs to one or more categories, these categories appear at the bottom of the page (or in the upper-right corner, depending on your screen).
The category pages themselves contain 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 usual place to add it is at the bottom of the page.
To link a category page within a page as a normal wiki link (without adding the page to the category), prefix the link name with a colon. For example: [[:Category:Not in this category]].
