Projecting the US map

In this recipe we are going to start with projecting the US map using D3 geo API, while also getting familiar with a few different JSON data formats for describing geographic data. Let's first take a look at how geographic data are typically presented and consumed in JavaScript.

GeoJSON

The first standard JavaScript geographic data format we are going to touch upon is called GeoJSON. GeoJSON format differs from other GIS standards in that it was written and is maintained by an Internet working group of developers.

GeoJSON is a format for encoding a variety of geographic data structure. A GeoJSON object may represent geometry, a feature, or a collection of features. GeoJSON supports the following geometry types: Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, and GeometryCollection. Features in GeoJSON contain a geometry object and additional properties, and a feature collection represents a list of features.

Source: http://www.geojson.org/

GeoJSON...