 A notable offspring of GeoJSON is TopoJSON, an extension of GeoJSON that encodes geospatial topology and that typically provides smaller file sizes.The GeoJSON format working group and discussion were begun in March 2007 and the format specification was finalized in June 2008.In April 2015 the Internet Engineering Task Force has founded the "Geographic JSON working group" which released GeoJSON as RFC 7946 in August 2016.