When used with the "Redirect category shell" (Rcat shell) template:
This page is a redirect. The following categories are used to track and monitor this redirect:
From a draft: This is a redirect from a draft page in the draft namespace or a userspace draft to the published article in mainspace. This redirect page must not be in mainspace.
When appropriate, protection levels are automatically sensed, described and categorized.
Template {{Redirect category shell}} may be used to add one or more rcat templates, along with their parameters and categories, to a redirect. For more information see the documentation page below.
When used by itself:
From a draft: This is a redirect from a draft page in the draft namespace or a userspace draft to the published article in mainspace. This redirect page must not be in mainspace.
This page is a redirect. The following categories are used to track and monitor this redirect:
From a page move: This is a redirect from a page that has been moved (renamed). This page was kept as a redirect to avoid breaking links, both internal and external, that may have been made to the old page name.
From a subpage: This is a redirect from a subpage. In a page title, a subpage name appears after a forward slash (/); for example, "Wikipedia:WikiProject Cricket/Articles", which is a subpage of "Wikipedia:WikiProject Cricket", redirects to Template:CricketRecentChanges. Not all articles or other pages with "/" in their titles are subpages (e.g. CP/M).
If this redirect is in mainspace, then it will populate the Redirects with old history category bold-linked above; if in any other namespace, then Category:Redirects from subpages will be populated.