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Community Basemap Program is an Esri initiative to create a worldwide, authoritative map.
Community Basemap Program has created a collection of creative commons licensed global maps, created from an amalgamation of authoritative and commercial data sources. Despite the commercial source of some of the data Esri is still able to provide it for free non-commercial usage. 
The datasets are built from a variety of sources including Esri itself, Lansat, TeleAtlas and many more.  The data is converted to fit a template by the data owners, with the templated data then joined up by Esri to create the global maps that form the community basemaps. Data holders are able to submit their data to Esri over the internet for attempted submission to the Community Basemap Project maps. 
There is an online GIS app which uses the community basemaps along with other basemaps which anyone may use for non-commercial purposes.
Community Basemap Program was released in July 2010.