Geospatial Mapping width D3
GeoJSON
Is a format for enconding geographical data (…) can represent cities, countries and roads.
TopoJSON
Is an extension of GeoJSON.
D3
Uses TopoJSON with the help of the client library.
Projections
Define how geographical data is represent on a flat surface.
Choropleths
npm install -g topojson
geo2topo custom.geo.json > custom.topo.json