The World Air Quality Index REST API allows developers to access and integrate the functionality of the index with other applications and websites. Some example API methods include geo-based queries, retrieving air quality data for cities and regions, and retrieving current weather conditions. The World Air Quality Index project is a social enterprise project started in 2007. The mission is to promote air pollution awareness and provide a unified air quality information for places around the world. The project is providing air quality information for more than 70 countries, covering more than 9000 stations in 600 major cities, via those two websites: aqicn.org and waqi.info.