How can I categorize pages?
Any page can be put in a category by editing the page and adding a link to the category. Just type [[Category:]], and put the name of the category between the colon and the brackets.
You can create new categories just by typing a new name. Pages can belong to more than one category, by having multiple category tags on the page.
All categories will appear at the bottom of an article page, in a "Categories" box. Clicking the category name will take you to a Category description page which will list all articles and subcategories contained within that category. You may click "edit" on a category description page to add additional text or images to the top of the page above the subcategory lists, and to place the category in another category.
Please note, category description pages are not designed to carry general content - they do not get counted in article statistics, and will not be found via many Special pages.
How do I create subcategories?
A category becomes a subcategory when you edit the category description page to add a Category tag for a "higher level" category. There is no limit to the number of subcategories a category may contain, or to the number of levels of categories. It is possible (though rarely desirable) to create category "loops".
The root category on most wikis is called Template:Ifexist. It is good practice to build a complete Category Tree, ensuring that all categories on your wiki have a place as subcategories of Category:Browse or its descendants.
To create an internal link to a category page without placing the edited page into the category itself, you must put a colon before the word "Category":
Can I redirect a category to another category?
No - attempting to Redirect a category will not work correctly (though it is technically possible). What you can do is add a notice (such as Wikia:Template:Category redirect) to inform users that a different category name should be used on articles, and delete the old category once everything has been moved.
Where can I see the currently used categories?
You can see a list of all currently used categories for each Wikia at Special:Categories. This list also displays how many pages are within each category.
You can reach this page by clicking the word "Categories" at the beginning of the box at the bottom of any categorized article, or by clicking "Special pages" in the sidebar.
What is the Category Tree extension?
The extension also adds the ability to expand subcategories on a category page, allowing you to see further subcategories.
- Wikimedia's Meta-Wiki's help page on categories for detailed information on categories.