View source for Category hierarchies

You can include a page in a category by inserting a link tag near the bottom of the page. For example, <nowiki>[[Category:British infantry battalions]]</nowiki> adds a page to [[:Category:British infantry battalions]].

For a list of all categories, see [[Special:Categories]].

Important things to remember:

* Wiki categories are hierarchical. They don't work like tags. Please don't flood higher level categories with pages that would fit better in a more specific category. The hierarchies are described below. You can also navigate through the category hierarchies by clicking the links to other categories on a category's page.
* Categories on this wiki are more flexible than the infobox data. The main aim is to make pages easier to find, not to strictly classify them. Categories do not necessarily match types in the infoboxes. Pages can be added to lots of different categories at the same time, and you can easily create new categories to organise pages in different ways.

== Top level categories ==

* [[:Category:Units|Units]] arranges units by type.
* [[:Category:Places|Places]] arranges pages geographically.
* [[:Category:Themes|Themes]] arranges pages by themes that don't fit the hierarchies for units or places, such as women's history.
* [[:Category:Sources|Sources]] is about documents you can use or that need linking to units.
* [[:Category:To do|To do]] lists pages that give details of things that need doing, and sub-categories of pages that need specific improvements.
* [[:Category:Help|Help]] pages give more information about how to use the site.

== Units and Countries ==

[[:Category:Units]] has the sub-categories which contain definition pages for each type of unit:

* [[:Category:Type definitions]] for general types (eg [[Infantry]]) used as values in the '''type''' field of {{tl|infobox military unit}}
* [[:Category:Specific type definitions]] for specific types (eg [[Infantry battalion]]) used as values in the '''specific_type''' field of {{tl|infobox military unit}}

There is also a category for each general type, eg [[:Category:Infantry units]].

[[:Category:All units]] lists every unit that has a page. This is mainly used to keep track of how many units have pages. It can also be used to export all unit pages via [[Special:Export]].

Units are also categorised by the type of unit and the country they came from. There are two hierarchies &ndash; one arranged by unit types, the other by countries and services &ndash; that typically join together in a category that combines a country and a general type of unit.

{| class="wikitable"
|-
|rowspan="2"|[[:Category:Units|Units]]
|[[:Category:Places|Places]]
|-
|[[:Category:Countries|Countries]]
|-
|rowspan="2"|[[:Category:Infantry units|Infantry units]]
|[[:Category:United Kingdom|United Kingdom]]
|-
|[[:Category:British Army|British Army]]
|-
|colspan="2"|[[:Category:British infantry units|British infantry units]]
|}

There are sometimes more specific categories below this, but this varies according to army size. See the headings below:

=== Large armies ===

These currently include:

* American
* British
* French

India is mostly similar but has some differences, [[#India|see below]].

Each army should have a category (eg [[:Category:British Army]]) that contains general pages about that army and more specific sub-categories for unit pages. Most unit pages should not be put directly in the army category but it can contain the highest levels. For example, [[:Category:British Army]] directly contains administrative corps and tactical expeditionary forces. As well as more 
specific sub-categories, there is a category for all units of that army (eg [[:Category:All British Army units]]).

Categories for unit types usually go down to a combination of country and specific type because there are often large numbers of units of each specific type. For example:

{| class="wikitable"
|-
|rowspan="2"|[[:Category:Units|Units]]
|[[:Category:Places|Places]]
|-
|[[:Category:Countries|Countries]]
|-
|rowspan="2"|[[:Category:Infantry units|Infantry units]]
|[[:Category:United Kingdom|United Kingdom]]
|-
|[[:Category:British Army|British Army]]
|-
|colspan="2"|[[:Category:British infantry units|British infantry units]]
|-
|colspan="2"|[[:Category:British infantry battalions|British infantry battalions]]
|}

Sometimes there are more categories below the specific category at the bottom of the above table. These contain subsets of their parent category, but unit pages will appear at both levels. eg [[1st Battalion, Rifle Brigade, British Army]] is a direct member of both [[:Category:British infantry battalions]] ''and'' [[:Category:British rifle battalions]].

Some units can be placed directly in the country + general type category if they don't fit easily in a specific type category. For example, some units are direct members of [[:Category:British machine gun units]].

=== Medium armies ===

These currently include:

* Australian
* Canadian
* New Zealand
* Portuguese

Each army's main category (eg [[:Category:Australian Army]]) directly contains:

* every unit page for that army
* general pages about that army
* more specific sub-categories for unit pages

The more specific sub-categories can combine either general type or specific type with the country.

For example, infantry battalions tend to be treated in a similar way to large armies because there can be large numbers of them:

{| class="wikitable"
|-
|rowspan="2"|[[:Category:Units|Units]]
|[[:Category:Places|Places]]
|-
|[[:Category:Countries|Countries]]
|-
|rowspan="2"|[[:Category:Infantry units|Infantry units]]
|[[:Category:Australia|Australia]]
|-
|[[:Category:Australian Army|Australian Army]]
|-
|colspan="2"|[[:Category:Australian infantry units|Australian infantry units]]
|-
|colspan="2"|[[:Category:Australian infantry battalions|Australian infantry battalions]]
|}

Other types of units are often in categories based on general type because there aren't as many of them. For example:

{| class="wikitable"
|-
|rowspan="2"|[[:Category:Units|Units]]
|[[:Category:Places|Places]]
|-
|[[:Category:Countries|Countries]]
|-
|rowspan="2"|[[:Category:Medical units|Medical units]]
|[[:Category:Australia|Australia]]
|-
|[[:Category:Australian Army|Australian Army]]
|-
|colspan="2"|[[:Category:Australian medical units|Australian medical units]]
|}

Australia also has extra categories just for the AIF: see [[:Category:Australian Imperial Force]].

=== Small armies ===

These currently include all parts of the British Empire except Australia, Canada, India, New Zealand, South Africa and the United Kingdom.

These don't usually have a category for the army or a category combining country and type. All units go directly under the country category, eg [[:Category:Nigeria]].

[[:Category:British Empire]] has sub-categories based on types, eg [[:Category:British colonial infantry units]].

=== Special cases ===

==== India ====

Mostly treated as a large army, but doesn't use an army category because some units were separate from the Indian Army and because there was no navy. Sub-categories for Indian units should go directly under [[:Category:India]].

All Indian units, whether Indian Army or Imperial Service Troops, can also be found in [[:Category:All Indian units]].

==== South Africa ====

On the boundary between small and medium, and army units split between Union Defence Force and the Overseas Expeditionary Force. For these reasons, unit sub-categories should go directly under [[:Category:South Africa]].

[[:Category:All South African units]] includes every Union Defence Force and Overseas Expeditionary Force unit that has a page.

== Units and sources ==

[[:Category:Units and sources]] is a child of both [[:Category:Units]] and [[:Category:Sources]]. It lists sub-categories that group units by what sources and media they have or need. Some of these sub-categories are also children of [[:Category:Pages needing attention]].

[[Category:Help]]