MD5 - Message Digest Algorithm is an old Cryptographic Hash Function which is developed by Ron Rivest in 1991.
MD5 gives a 16 byte or 128 bits hash value, and has 32 digits Hexadecimal number. MD5 is used to store a one way hash of a password, also with key stretching. MD5 is used in the fields of electronic discovery, in order to provide a unique identifier for each document that is exchanged during the legal discovery process.