What3words

what3words is a system for identifying locations on the Earth's surface by a group of three words, each such combo corresponding to a 3-by-3 meter square. It is intended as an addressing system to replace such things as street addresses and latitude-and-longitude coordinates, and is actually being used by the postal system in Mongolia for this purpose. Its system is proprietary, and they have used takedown notices in an attempt to squelch open-sourced reverse-engineered implementations of it, causing some flack. One such implementation, WhatFreeWords, was taken down via a domain-name-dispute process and has even been excluded from Internet Archive's Wayback Machine.

In addition to copyrights and trademarks, various patents are claimed in many countries, though somebody claims to have created and published prior art.

The algorithm uses a list of 40,000 words and a system of dividing the world into blocks and doing mathematical calculations on their coordinates to ultimately yield three indices into that list, where nearby points have totally different words connected with them.

A number of parody systems have been created to make fun of this, including What3Emojis and What3Pokemon. What3Words would probably find all of them to infringe their intellectual property.

Open Street Map has disallowed adding What3Words identifiers anywhere in their system due to their proprietary nature.

Official sites and apps

 * Official site
 * Interactive map
 * Developer site
 * API docs
 * iOS app
 * Android app

Independent implementations

 * WhatFreeWords (offline; even the Wayback Machine has taken it down)
 * Description of algorithm in WhatFreeWords site (offline; even the Wayback Machine has taken it down)

Other External Links

 * Openstreetmap Wiki: What3words
 * Criticism, why such a system is not suitable