This template checks whether the current page is a subpage or not. A subpage is a page that has a slash:

[[Template:Parentpage/Subpage]]

Exception: in article space (mainspace) the slash is part of the title, and there are no subpages. Example, AC/DC is a parent page not a subpage.

Usage example: both Template:Infobox element isotopes and Template:Infobox element isotopes/infotable use documentation page Template:Infobox element isotopes/doc. We only want to categorise the parent page. So in the /doc page we add:

{{Subpage other|<!-- do not categorise -->|[[Category:Chemical element infobox]]}}
Note
WP:Subpage uses an other definition than magic word {{SUBPAGENAME}}. This template uses the former definition (pagename has an after-slash part).

See also

mali niŋ
  • {{Sandbox other}} — Distinguishes between the /sandbox subpages and the root template page and other subpages.
  • {{Testcases other}} — Distinguishes between the /testcases subpages and the root template page and other subpages.
  • {{Template other}} — Distinguishes between pages in the template namespace and other namespaces.
  • {{When on basepage}} — Distinguishes between the root template page and subpages, without special consideration in the mainspace.
  • {{Subpage other}} — Distinguisheds between the root page and subpages (any subpage), classifying pagenames in the mainspace with a slash as being the root page.