# Locality-preserving hashing

In computer science, a **locality-preserving hashing** is a hash function *f* that maps a point or points in a multidimensional to a scalar value, such that if we have three points *A*, *B* and *C* such that

In other words, these are hash functions where the relative distance between the input values is preserved in the relative distance between of the output hash values; input values that are closer to each other will produce output hash values that are closer to each other.

This is in contrast to cryptographic hash functions and checksums, which are designed to have .

Locality preserving hashes are related to and .