A geocode is a code that represents a geographic entity (location or object). It is a unique identifier of the entity, to distinguish it from others in a finite set of geographic entities. In general the geocode is a human-readable and short identifier. Typical geocodes and entities represented by it: Geocodes are mainly used (in general as an atomic data type) for labelling, data integrity, geotagging and spatial indexing. In theoretical computer science a geocode system is locality-preserving hashing function.