Message Authentication Code
In cryptography, a message authentication code (MAC) algorithm (also keyed-hash function) is an algorithm for generating a short string of information used to authenticate a message. A MAC algorithm involves a one-way hash function or block cipher and accepts a secret key as well as a message as input and produces a MAC (sometimes known as tag). The purpose of the code is to ensure the authenticity as well as the integrity of a message in transit.
Popular MAC algorithms include HMAC, OMAC and PMAC.
