We have the tag cipher having 103 questions.
When should this tag be used, if ever? Isn't having encryption enough?
I don't really see a valid use for it.
If you want to talk about encryption in general, well, use encryption. If you want to talk about specific kinds of ciphers, use block-cipher, stream-cipher or classical-cipher (and/or one of the more specific tags we have for subsets of those). I don't see much of a gap between those.