Wikipedia:Overcategorization

Categorization is a useful tool to group articles for ease of navigation, and correlating similar information. However, not every verifiable fact (or the intersection of two or more such facts) in an article requires an associated category. For lengthy articles, this could potentially result in hundreds of categories, most of which aren't particularly relevant. This may also make it more difficult to find any particular category for a specific article. Such overcategorization is also known as "category clutter".

To address these concerns, this page lists types of categories that should generally be avoided. Based on existing guidelines and previous precedent at , such categories, if created, are likely to be deleted.

One of the central goals of the categorization system is to categorize articles by their defining characteristics:

A central concept used in categorising articles is that of the defining characteristics of a subject of the article. A defining characteristic is one that reliable sources commonly and consistently define the subject as having—such as nationality or notable profession (in the case of people), type of location or region (in the case of places), etc.

Categorization by non-defining characteristics should be avoided. It is sometimes difficult to know whether or not a particular characteristic is "defining" for any given topic, and there is no one definition that can apply to all situations. However, the following suggestions or rules-of-thumb may be helpful:

Often, users can become confused between the standards of notability, verifiability, and "definingness". Notability is the test that is used to determine if a topic should have its own article. This test, combined with the test of verifiability, is used to determine if particular information should be included in an article about a topic. Definingness is the test that is used to determine if a category should be created for a particular attribute of a topic. In general, it is much easier to verifiably demonstrate that a particular characteristic is notable than to prove that it is a defining characteristic of the topic. In cases where a particular attribute about a topic is verifiable and notable but not defining, or where doubt exists, creation of a list article is often the preferred alternative.

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