geojson

GeoJSON is a format for encoding geographic data structures using JSON (JavaScript Object Notation). It represents simple geographical features, their attribute data, and the coordinate reference system used to locate them. The format defines three principal object types: geometry objects (Point, LineString, Polygon, MultiPoint, MultiLineString, MultiPolygon, GeometryCollection), Feature, and FeatureCollection. A geometry object has a type and coordinates. A Point uses a single coordinate pair; a LineString uses an array of positions; a Polygon uses an array of linear rings; multi-geometries use arrays of the corresponding simple geometries; a GeometryCollection groups arbitrary geometry objects. A Feature combines a geometry with a properties object and an optional id. A FeatureCollection is a collection of Feature objects.

Coordinates are expressed as numbers in a geographic coordinate system, with longitude, latitude order and optional altitude. Per RFC 7946, the CRS member is deprecated; coordinates are in the default WGS84 geographic coordinate system, encoded in decimal degrees. Optional bounding box ('bbox') may be included at any level.

GeoJSON is text-based, human-readable, and widely supported in web mapping libraries (such as Leaflet and OpenLayers) and GIS tools, making it a common data interchange format for geospatial data between servers and clients.

Limitations include lack of topology or curved geometries and potential verbosity for large datasets. For topology-aware or compact representations, formats such as TopoJSON or binary encodings may be used in addition to GeoJSON.