A cryptographic algorithm that computes a numerical value based on a data file or electronic message. The numerical value is used to represent that file or message, and depends on the entire contents of the file or message. A hash function can be considered to be a fingerprint of the file or message. Colloquially known as a hash, hash function, or digital fingerprint. Hashes provide integrity protection.
Source: Election Terminology Glossary - Draft, National Institute of Standards and Technology (NIST), https://pages.nist.gov/ElectionGlossary/