GeoJSON is a JSON data format specification to encode and represent geographic location data with respect to the standard coordinate system for the Earth

1. GeoJSON
• GeoJSON is a data format for encoding a variety of geographic data structures
• GeoJSON data structure represents a geometry, a feature, or a collection of features
• GeoJSON supports the seven Geometry types/objects:
1. Point
2. LineString
3. Polygon
4. MultiPoint
5. MultiLineString
6. MultiPolygon
7. GeometryCollection
• Any implementations must not change the semantics of GeoJSON members and types
• GeoJSON feature (Feature) object contains a Geometry object and additional
properties
• GeoJSON feature collection (FeatureCollection) object represents a list of Feature
objects

2. GeoJSON
• GeoJSON’s data structure is represented as a JSON object
• GeoJSON object is a JSON object
• GeoJSON object represents a Geometry, Feature, or collection of Features
• GeoJSON object is a collection of name/value pairs, called as members
• In a GeoJSON object, name is always a string
• In a GeoJSON object, value can be string, number, object, array, boolean, or
null
• If a GeoJSON object has a member with the name "type", then the value of the
member must be one of the GeoJSON types
• If a GeoJSON object may have a "bbox" member, then the value of the
member must be a bounding box array

3. Geometry Object
• Geometry object represents points, curves, and surfaces
in coordinate space
• Every Geometry object is a GeoJSON object
• The value of a Geometry object’s "type" member must be
one of the seven Geometry types
• The value of Geometry object’s "coordinates" member is an
array
• The GeoJSON "coordinates" and "geometries" members
define Geometry objects

4. Feature Object
• Feature object represents a spatially bounded thing.
• A GeoJSON object with the type "Feature" is a Feature object
• Every Feature object is a GeoJSON object
• Feature object has a "type" member with a value of "Feature"
• If a Feature object has a member with the name "geometry", then the value of the
geometry member must be a Geometry object or JSON null value (unknown location/
Feature)
• If a Feature object has a member with the name "properties", then the value of the
properties member is an object (any JSON object or JSON null value)
• If a Feature has a commonly used identifier, then it should be included as a member of the
Feature object with the name "id" and the value must be either a JSON string or number
• The GeoJSON "geometry" and "properties" members define a Feature object

5. FeaturesCollection Object
• A GeoJSON object with the type
"FeatureCollection" is a FeatureCollection object.
• A FeatureCollection object has a member with the
name "features" and the value of the "features"
member must be a JSON array, where each array
element of the array is a Feature object
• The GeoJSON "features" member defines a
FeatureCollection object

6. Bounding Box
• Bounding Box also known as the
Minimum Bounding Rectangle (MBR)
or Envelope
• Bounding Box is a Rectangle, oriented
to the x and y axes, which bounds a
geographic feature or a geographic
dataset
• Bounding Box is specified by two
coordinates: xmin, ymin and xmax,
ymax
• GeoJSON object may have a member
named "bbox" to include information
on the coordinate range for its
Geometries, Features and
FeatureCollections.

7. Resources
• GeoJSON website
• GeoJSON specification
• JSON specification
• Internet JSON specification
• OpenGIS Simple Features Implementation Specification for SQL
• Unlocking the Mysteries of Bounding Box by Douglas R. Caldwell
• Uniform Resource Identifier for Geographic Locations
• World Geodetic System 1984
• NIMA Technical Report TR8350.2, "Department of Defense World Geodetic System 1984, Its
Definition and Relationships With Local Geodetic Systems", Third Edition, 4 July 1997
• Open Geospacial Consortium