Editing Incubator escapee wiki:Categorization (section)

== Categorizing project pages <span class="anchor" id="Non-article and maintenance categories"></span><span class="anchor" id="Maintenance categories"></span><span class="anchor" id="Administrative category"></span><span class="anchor" id="PROJCATS"></span> ==
{{Shortcut|WP:PROJCATS}}
===Wikipedia administrative categories ===
{{see|Wikipedia:Administration#Data structure and development|Wikipedia:Wikipedia namespace}}
{{see also|Category:Wikipedia administration}}
A distinction is made between two types of categories:
* Administrative categories{{snd}}intended for use by editors or by automated tools, based on features of the current state of articles, or used to categorize non-article pages.
* Content categories{{snd}}intended as part of the encyclopedia, to help readers find articles, based on features of the subjects of those articles.

Administrative categories include '''stub categories''' (generally produced by [[Wikipedia:Stub|stub]] templates), '''maintenance categories''' (often produced by [[Wikipedia:Template_index#Article-related_namespace|"cleanup" templates]] such as {{tl|cleanup}} and {{tl|fact}}, or those used for [[Wikipedia:Maintenance|maintenance]] projects), and '''categories of pages in non-article [[Wikipedia:Namespace|namespaces]]''', such as [[Wikipedia:WikiProject|WikiProject]] [[Wikipedia:Assessment|assessment]] [[:Category:Articles by quality|categories]] and [[:Category:Wikipedia policies and guidelines|categories]] holding [[Wikipedia:Policies and guidelines|Wikipedia policies and guidelines]].

Article pages should be kept out of administrative categories if possible. For example, the templates that generate WikiProject and assessment categories should be placed on talk pages, not on the articles themselves. If it is unavoidable that an administration category appears on article pages (usually because it is generated by a maintenance template that is placed on articles), then in most cases it should be made a '''hidden category''', as described in [[#Hiding categories|§&nbsp;Hiding categories]] below.

There are separate administrative categories for different kinds of non-article pages, such as [[Wikipedia:Project namespace|project page]] categories, [[Wikipedia:Template|template]] categories, [[Wikipedia:Disambiguation page categories|disambiguation page categories]], etc.

In ''maintenance categories'' and other ''administrative categories'', pages may be included regardless of type. For example, in an error tracking category it makes sense to group templates separately, because addressing the errors there may require different skills compared to fixing an ordinary article. For sorting each namespace separately, see [[#Sort keys|§&nbsp;Sort keys]] below.

=== Files <span class="anchor" id="FILECAT"></span><span class="anchor" id="Images"></span><span class="anchor" id="Files/images"></span> ===
{{shortcut|WP:FILECAT}}{{see|Wikipedia:Manual of Style/Images#Image description pages}}
Category tags should be added to [[Help:Files|file]] pages of files that have been uploaded to Wikipedia. When categorized, files are not included in the count of articles in the category, but are displayed in a separate section with a thumbnail and the name for each. A category can mix articles and images, or a separate file/image category can be created. A file category is typically a subcategory of the general category about the same subject, and a subcategory of the wider category for files, [[:Category:Wikipedia files]]. To categorize a new file when uploading, simply add the category tag to the [[Help:Edit summary#File upload summary|upload summary]].

Freely licensed files should be uploaded to, and categorized on, [[WP:COMMONS|Wikimedia Commons]], instead of uploading and categorizing on Wikipedia. Existing freely licensed files should usually be moved from Wikipedia to Commons, with a mirror page automatically remaining on Wikipedia. (For an example of one such mirror page, see [[:File:Niederwald memorial 2.JPG|here]].) Categories should not be added to these Wikipedia mirror pages, because doing so creates a new Wikipedia page that is subject to [[WP:SD#F2|speedy deletion]]. Exceptions to this principle are made for mirror pages of images that are nominated as [[Wikipedia:Featured pictures|featured pictures]] and for those that appear on the Wikipedia [[Main Page]] in the [[:Template:Did you know|Did You Know?]] column.

Images that are used in Wikipedia that are [[Wikipedia:Non-free content|non-free or fair use]] should not appear as thumbnail images in categories. To prevent the thumbnail preview of images from appearing in a category, <nowiki>__NOGALLERY__</nowiki> should be added to the text of the category. In such cases, the file will still appear in the category, but the actual image preview will not.

=== Templates <span class="anchor" id="TEMPLATE"></span><span class="anchor" id="TEMPLATES"></span><span class="anchor" id="TEMP"></span><span class="anchor" id="T"></span> ===
{{shortcut|WP:CAT#T}}{{See also|Template:Documentation}}
[[Wikipedia:Template namespace|Templates]] are not articles, and thus do not belong in ''content categories''. It is however a recommendation to place them in '''template categories''' – subcategories of [[:Category:Wikipedia templates]] – to assist when looking for templates of a certain type. For example, [[:Template:Schubert string quartets]] is categorized under [[:Category:String quartets by composer navigational boxes]], which should be a subcategory of [[:Category:Music navigational boxes]] (type) but [[:Template:Schubert string quartets]] should ''not'' be categorized under [[:Category:Franz Schubert]] or [[:Category:String quartets]] (content).

Pages using a template should rarely be placed in the same categories as the template itself. To ensure this separation, the category for the template should be placed on the template's documentation page, normally after the two pipes in a <syntaxhighlight lang=wikitext inline><includeonly>{{Sandbox other||...}}</includeonly></syntaxhighlight> block. Because template documentation is rarely [[Wikipedia:Protection policy|protected]], template categorization can be modified by all editors even when the template code itself is protected from editing by most editors. When there is no documentation page, the category for the template may be placed at the bottom of the template itself, within a {{tag|noinclude}} block. There should be no spaces or new lines between the last part of the template proper and the opening {{tag|noinclude|o}} tag.

===User pages <span class="anchor" id="Categorizing user pages"></span><span class="anchor" id="USER"></span><span class="anchor" id="USERS"></span><span class="anchor" id="USERNOCAT"></span> ===
{{shortcut|WP:CAT#USER|WP:USERNOCAT}}{{Further|Wikipedia:User categories|Wikipedia:User pages#Categories, templates that add categories, and redirects}}

[[Wikipedia:User pages|User pages]] are not articles and thus do not belong in ''content categories'' such as [[:Category:Living people|Living people]] or [[:Category:Biologists|Biologists]]. Similarly, [[#Draft]] versions of articles should be kept out of content categories. Also, do not [[Help:Transclusion|transclude]] articles into your user pages, as this will result in the page being included in all the article's categories.

However, user pages ''can'' be placed in '''user categories''' – subcategories of [[:Category:Wikipedians]], such as [[:Category:Wikipedian biologists]] – which assist collaboration between users. And certain [[WP:SP|user sub-pages]] that are non-article drafts, are permitted in [[#PROJCATS|project categories]], like [[:Category:User essays]]. 

A list of article-space categories with user pages, is maintained at [[WP:Database reports/Polluted categories|Database reports/Polluted categories]].