I've had a look at some tags related for cryptographic algorithms. Here are several related minor issues. We should decide on which tag names we prefer, then retag or synonymize as desired.
3DES: tripledes should be a synonym of 3des (the latter has a lot more uses and a tag wiki).
Rijndael/AES: Should rijndael be a synonym of aes? Strictly speaking, Rijndael is a superfamily of AES, but in practice they are used almost interchangeably.
chaining: We have ecb and cbc-mode. Which naming form is better?
md5_file: Is it worth having a separate tag for md5-file, and if so, should it be reserved for the
md5_file function in PHP?
SHA1 or SHA-1: We have both sha-1 and sha1. They should be merged, in which direction? Ditto for sha-512 and sha512.
SHA-2: We have separate tags for sha2, sha256 and sha512. Should they be folded into sha-2, or should they remaine separate?
hmacsha1: Should hmacsha1 remain, or should it be transformed to hmac+sha-1?
See Merge tags: [pkcs11] and [pkcs#11]