Certain category groups have special uses or requirements.
Geographic based categories[change source]
Categories that are based on geography and nationality (for example, Category:Towns in Germany, Category:Buildings and structures in London and Category:Chinese people) all use the same basic structure. Nationality categories are sub-categories of their associated geography categories (Category:English people is a sub-category of Category:England) as well as what ever other categories apply (Category:English people is also a Category:People based category so it is a sub-category of Category:British people
The top level of each category is based on the continent it is a part of. The next level would be Country. Each country is seperatd into the major sub-division of that country (states, regions and provinces) and then smaller subdivisions (counties). This is repeated down until the municipality level (city, town) is reached.
Categories are only separated down to the point there is enough articles to need it. The municipality level is usually only needed for the largest of cities. In some cases, steps between categories can be skipped. For example, in most countries, the city category is a part of the country category because there is not enough need for the steps in between.
Country subdivisions[change source]
A sample of commonly seen country sub-divisions is seen below.
- Raleigh is a city in the American state of North Carolina. The city is in Wake County. The category set-up for it is Category:Wake County, North Carolina (it's county) -> Category:North Carolina counties (in Category:North Carolina, it's state) -> Category:Counties in the United States (in Category:United States, it's country) -> Category:North America (it's continent}}. Category:Raleigh, North Carolina (the city itself}} does not exist because there is currently no need for it. If it did exist, it would be a sub-category of the county category (Wake County, North Carolina).
- Big Ben is a clock tower in London. Its category set-up is Category:Buildings and structures in London -> Category:Buildings and structures in England -> Category:Buildings and structures in the United Kingdom -> Category:Buildings and structures in Europe.
The United Kingdom[change source]
The United Kingdom is a special case. It includes the countries of England, Scotland, Wales and Northern Ireland as well as many other areas. Many of these areas do not have their own categories. Another problem is that if something is termed "British" (from the United Kingdom), it may not be possible to know if it is actually one of the countries which make up the United Kingdom. If the actual country is known, it should be used. If it is not known, the British/United Kingdom level should be used.
Musical entertainers[change source]
The Category:Musical entertainers is used to group all entertainers who deal with music. It is not uncommon for a country to not have enough articles on musical entertainers to support all categories. In this case, Musicians is normally the main category as all other sub-categories can be described by it in one form or another (Singer are musicians who use their voice as their instrument, songwriters and composers almost always play an instrument). Once enough articles are available, these groups should be separated from musicians. Once enough subcategories and solo articles (for example, singers, musicians and an article on a composer) then Musical entertainers should be created.
Main level[change source]
The main category includes sub-categories for singers, songwriters, musicians, bands, composers and conductors. The category is broken down into each of these major groups as well as Category:Musical entertainers by nationality.
Secondary levels[change source]
The secondary levels (the sub-categories) are mainly broken down into a combination of nationality and occupation. Examples of this are Category:English singers and Category:German musicians. The categories use the same basic set-up for nationality as the Geography categories.
Singers are a special case. While they are technically musicians, they are listed in a category independent of musicians, but still under musical entertainers. Singer categories should never be a sub-category of a musicians category. People notable for singing should only be in musician category if no separate singers category exists (or should exist). This does not apply to singers who are also notable as musicians. These people are normally placed in the musician category for their notable instrument. For example a Italian singer who is also notable for playing guitar would be in the appropriate categories for both singers and guitarists (a musicians category). Many singers also play an instrument, but they are usually only notable for their singing so care should be used when placing them in a category based on the instrument.
Standard categories[change source]
Many topics have types of categories which usually apply to every article in the topic. For example, Movies should all have a category for the year they were released, the genre(s) of the movie, and its country of origin.
Some of these topics include: