MD6 stands for 'Message Digest algorithm 6'. MD6 algorithm is a cryptographic hash function It uses a Merkle tree-like structure to allow for immense parallel computation of hashes for very long inputs.
SHA-1 (Secure Hash Algorithm 1) is a cryptographic hash function which takes an input and produces a 160-bit (20-byte) hash value known as a message digest – typically rendered as a hexadecimal number, 40 digits long.
MD5 stands for 'Message Digest algorithm 5'. MD5 algorithm is used as a cryptographic hash function or a file fingerprint. Often used to encrypt password in database, MD5 can also generate a fingerprint file to ensure that a file is the same after a transfer.