We need to make these tag naming decisions (mostly together with synonyms).
✔ It looks like gnupg is better. (Done.)
✔ It looks like cipher is the only widely used spelling in cryptographic context. (Done.)
How to tag questions about differential cryptanalysis? differential-cryptanalysis is one character too long (maximum length is 25, and this is not likely to change just for us). For now we have differential, which is not really optimal here.
➾ Is there some useful abbreviation, which still is recognizable?
✘ Seems like differential-analysis is okay.
✔ I changed the tag on the only question, and differential got autodeleted now. (Do we need a synonym here?)
While technically TLS is a different protocol than SSL, they are quite similar (TLS 1.0 is more similar to SSL 3.0 than SSL 3.0 to SSL 2.0), and often implementations know (versions of) both protocols.
SSL is the preferable tag name since the acronym is more known than TLS. (I'm just now writing a tag wiki excerpt + tag wiki which mentions both names.)
✔ (synonym made.)
➾ Which one do we prefer (or better some even other name)?
✔ After Thomas' answer (and noone who later said something against it), I just merged both of these as public-key.
(I mark here what seems community consensus as ✘, and what is done with ✔.)
I now mark this as completed, as the initial bag of tag names seems to be done. Open a new question for new ones, this will provide better visibility.