What3words is a geocode system for the communication of locations with a resolution of three metres. What3words encodes geographic coordinates into three dictionary words; the encoding is permanently fixed. For example, the omphalos of Delphi, believed by the ancient Greeks to be the centre of the world, is located with ///spooky.solemn.huggers. What3words differs from most other location encoding systems in that it displays three words rather than strings of numbers or letters.
What3words has a website, apps for iOS and Android, and an API that enables bidirectional conversion between what3words addresses and latitude/longitude coordinates. As the system relies on a fixed algorithm rather than a large database of every location on earth, it works on devices with limited storage and no Internet connection.
According to the company its revenue comes from charging businesses for high-volume use of the API that converts between 3 words and coordinates; services for other users are free of charge.