Hash Function

In general, a hash function is a mathematical procedure used to translate a specific type of data into a smaller length. The values it returns may be called hash values, hash sums, hash codes or just hashes. A hash function is mostly used to enhance the process of a table lookup or the task of data comparison. This may include detecting items in a database or finding duplicate records. Hash functions are often associated with checksums, check digits, error correcting codes, fingerprints or cryptographic hash functions. While the functions overlap to some extent, each has their own use and credentials. The HashKeeper, a database maintained by the NDIC (National Drug Intelligence Center), is better described as a repository of fingerprint files rather than hash values. Cryptographic hash functions such as MD5 have a stronger assurance of uniformity over checksums and fingerprints. This makes them a great choice for general purpose hash functions.