Hash Functions

Hashing is a one-way mapping of data. It takes a variable-length input and produces a fixed-length output called a message digest or simply a hash. Unlike encryption, which can be decrypted, hashes cannot be transformed back into the original message.

Graphic that shows sample hash values for some encrypted words and phrases. The left column shows variable-length inputs: the words “Students,” “Students are graded” and “Students are graduated.” Arrows lead to the middle column, which represents the cryptographic hash function that processes plain text and converts it to a hash value. Arrows also lead to the right column, called hash value or digest.