From a page move: This is a redirect from a page that has been moved (renamed) or is the result of a page move. One reason this page was kept as a redirect is to avoid breaking links, both internal and external, that may have been made to the old page name. Any redirect with a page move logged on its history page should be tagged with this rcat template.
To a help page: This is a redirect from any page inside or outside of help namespace to a page in that namespace.
The above category link leads to a list of redirects from inside help namespace. For redirects from outside help space, see Category:Redirects to help namespace.
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.
When appropriate, protection levels are automatically sensed, described and categorized.
