To a redirect category (rcat) template: This is a redirect from an alias/shortcut (usually), or from a redirect that is the result of a page move/rename, to a redirect category (rcat) template.
From a shortcut: This is a redirect from a shortcut in any namespace to a page in any namespace except template namespace.
Shortcuts are wikilinked on community pages, talk pages, and edit summaries, but not in mainspace articles.
When appropriate, protection levels are automatically sensed, described and categorized.