Help:Creating and Adding to Categories

How to create categories
Creating a category is as simple as adding a soft link to the appropriate article in the Category: namespace; for instance, to add Derek Jeter to a "2004 American League All-Stars" category, you would edit the Derek Jeter article and enter   at the bottom. Although the link will not appear in the article text, a page called Category:2004 American League All-Stars will automatically list alphabetically all articles that contain the   link. The appeal of categories is that unlike lists, they update themselves automatically, and that one can use them to quickly find related articles. However, categories are not a substitute for lists, and you will find that many articles belong to both lists and categories. You may see some inconsistencies when first creating the category: it may alternate between appearing empty and appearing with your first additions. It will probably correct itself in a few minutes.

Note that, although "uncreated" categories will correctly list articles that have been assigned to them, the category page itself does not exist until it is manually created. The easiest way to create the category page is to follow the edit link from an article and add a parent category and a category description as explained below.

Creating subcategories
Create subcategory pages by putting the name of the parent category on a category page that you would like to be the subcategory. Child categories (subcategories) are created by putting on the lower-level category pages. For example, on a (sub)category page called Category:Boston Celtics Players you put, Boston Celtics Players becomes a subcategory of NBA Players.

When adding an article to a category, or creating categories, one should be careful to use the correct categories and subcategories. Horizontal categorization refers to placing an article in the correct category while vertical categorization refers to placing an article in the correct subcategory.

When assigning an article into categories, try to be thorough. The topic may be associated with a team, a year, a college, a position, etc. You might need to poke around the category hierarchy a bit to find the right place. Try searching for articles similar to the article you are categorizing to get ideas or to find the most appropriate place. To see a list of all the categories that have been created already, click here. Whatever categories you add, make sure they do not implicitly violate the neutral point of view policy. If the nature of something is in dispute, you may want to avoid labelling it or mark the categorization as disputed. Most categorizations are pretty straightforward, though.

Making groups of subcategories
Categories can only list 200 entries at a time. When there are more than 200 entries, only the first 200 will be displayed. To make it easy to navigate, add a TOC (table of contents). TOCs are added by typing:
 *   - which adds a complete TOC (Top, 0 - 9, A-Z)
 *   - which adds a TOC without numbers. This is for categories with members that only start with letters.

When a given category gets crowded, also consider making several subcategories. Group similar articles together in a meaningful and useful way that will make it easy for readers to navigate later. Remember that several subcategorization schemes can coexist (for example, if Category:Software gets too big, you don't have to choose between subdividing it by function or subdividing it by platform, you can simultaneously subdivide it in both ways).

A set of related categories often forms a hierarchy or a nexus. This can take several different forms, all of which are welcome and encouraged:


 * A taxonomic grouping. For example, Category:South Asian countries is part of a geographical hierarchy.  Category:Academic disciplines catalogs divisions between fields of study.


 * A functional grouping. Examples: Category:Ancient Rome, Category:World War II, and Category:Commercial item transport and distribution.  These bring together articles and subcategories from different fields or taxonomies (history, war, culture, people, companies, industries, technologies) that have an interesting common thread.


 * Hybrid forms. For example, Category:Art is both part of the taxonomy of Category:Academia and a cross-reference point for lots of things that have little in common except that they have something to do with art.


 * Offshoot forms. For example, Category:Film stubs contains subcategories of Category:Comedy film stubs for comedy films, and Category:Drama film stubs for drama films.

Category membership and creation
When writing the description for a category, give it a parent category. In fact, you should try to give it at least two parent categories. For example, Category:British writers should be in both Category:Writers by nationality and Category:British people. A few categories do only merely subdivide their parent category, but unless the parent category has many potential articles under it, or many potential subdivisions, if you can't think of a second parent category, it might be a better idea to fold your smaller category into the parent.

Wikipedia namespace
Categories relating to the Wikipedia namespace should be added only to the talk page of articles. For example, tags suggesting the article is needs work, would be placed on the talk page as they are relevant to editors, not an aid to browsing in the way ordinary categories are.

User namespace
Categories relating to the User namespace should be added only to Wikipedia-specific categories. Users should not add their user pages to article namespace categories such as Category:People or other subcategories, Category:Biologists etc, which are reserved for pages in the article namespace. However, it is appropriate to add a user page to Wikipedia-specific categories such as Category:Wikipedians or other similar subcategories such as Category:Wikipedian musicians. (See also m:Help:Category for guidelines on category "pollution").

If you copy an article to your user namespace (for example, as a temporary draft or in response to an edit war) you should decategorize it.

Image namespace
See categorizing images.