From a related word or phrase: This is a redirect from a word or phrase (term) to a page title that is related in some way. This redirect might be a good search term, or it could be a candidate for a Wiktionary link.
Redirects from related words are not properly redirects from alternative spellings of the same word. They are also different from redirects that are subtopics or related topics, because unlike those, a related word or phrase probably does not warrant its own subtopic section in the target page or possess the possibility of ever becoming an article, template, project page, and so forth.
Mentioned in a hatnote: This is a redirect from a title that is mentioned in a hatnote at the redirect target. The mention is usually atop the target article. It may, however, be directly under a section header, or in another article's hatnote (whenever the hatnote is under a section, {{R to section}} should also be used).
The titles of redirects mentioned in hatnotes may refer to a subject other than that of the target page. It is possible that this redirect may need to be retargeted, or become an article under its own title (see {{R with possibilities}}). If the title is a good candidate for a Wiktionary link, it may also be added.
When appropriate, protection levels are automatically sensed, described and categorized.