> ## Documentation Index > Fetch the complete documentation index at: https://docs.wherobots.com/llms.txt > Use this file to discover all available pages before exploring further. # Geography Functions The `Geography` type in Sedona represents spatial objects on a spherical (geodesic) model of the Earth. Unlike the planar [Geometry](/reference/wherobots-db/geometry-data/geometry-functions) type, distance, area, and other measurements performed on `Geography` objects account for the curvature of the Earth and return results in real-world units (e.g., meters). ## Geography Constructors These functions create geography objects from various formats. | Function | Return type | Description | | :----------------------------------------------------------------------------------------------------- | :---------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [ST\_GeogFromEWKB](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogFromEWKB) | Geography | Construct a Geography from EWKB Binary. This function is an alias of [ST\_GeogFromWKB](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogFromWKB). | | [ST\_GeogFromEWKT](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogFromEWKT) | Geography | Construct a Geography from OGC Extended WKT. | | [ST\_GeogFromGeoHash](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogFromGeoHash) | Geography | Create Geography from geohash string and optional precision | | [ST\_GeogFromWKB](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogFromWKB) | Geography | Construct a Geography from WKB Binary. | | [ST\_GeogFromWKT](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogFromWKT) | Geography | Construct a Geography from WKT. If SRID is not set, it defaults to 0 (unknown). | | [ST\_GeogToGeometry](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeogToGeometry) | Geometry | This function constructs a planar Geometry object from a Geography. While Sedona makes every effort to preserve the original spatial object, the conversion is not always exact because Geography and... | | [ST\_GeomToGeography](/reference/wherobots-db/geometry-data/geography/constructors/ST_GeomToGeography) | Geography | This function constructs a Geography object from a planar Geometry. This function is intended for geometries defined in a Geographic Coordinate Reference System (CRS), most commonly WGS84 (EPSG:432... | ## Geography Functions These functions operate on geography type objects. | Function | Return type | Description | | :---------------------------------------------------------------------------------------------- | :---------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [ST\_Area](/reference/wherobots-db/geometry-data/geography/functions/ST_Area) | Double | Spherical area of a geography, in square meters. | | [ST\_AsEWKT](/reference/wherobots-db/geometry-data/geography/functions/ST_AsEWKT) | String | Return the Extended Well-Known Text representation of a geography. EWKT is an extended version of WKT which includes the SRID of the geography. The format originated in PostGIS but is supported by ... | | [ST\_AsText](/reference/wherobots-db/geometry-data/geography/functions/ST_AsText) | String | Well-Known Text (WKT) representation of a geography. | | [ST\_Buffer](/reference/wherobots-db/geometry-data/geography/functions/ST_Buffer) | Geography | Metric ε-buffer of a geography (distance in meters along the spheroid). | | [ST\_Centroid](/reference/wherobots-db/geometry-data/geography/functions/ST_Centroid) | Geography | Spherical centroid of a geography, as a Geography point. | | [ST\_Contains](/reference/wherobots-db/geometry-data/geography/functions/ST_Contains) | Boolean | Test whether geography A fully contains geography B. | | [ST\_DWithin](/reference/wherobots-db/geometry-data/geography/functions/ST_DWithin) | Boolean | Test whether two geographies are within a given geodesic distance (in meters). | | [ST\_Distance](/reference/wherobots-db/geometry-data/geography/functions/ST_Distance) | Double | Minimum geodesic distance between two geographies, in meters. | | [ST\_Envelope](/reference/wherobots-db/geometry-data/geography/functions/ST_Envelope) | Geography | This function returns the bounding box (envelope) of A. It's important to note that the bounding box is calculated using a cylindrical topology, not a spherical one. If the envelope crosses the ant... | | [ST\_Equals](/reference/wherobots-db/geometry-data/geography/functions/ST_Equals) | Boolean | Test whether two geographies are spatially equal. | | [ST\_GeometryType](/reference/wherobots-db/geometry-data/geography/functions/ST_GeometryType) | String | Type of a geography as a string (e.g., `ST_Point`). | | [ST\_Intersection](/reference/wherobots-db/geometry-data/geography/functions/ST_Intersection) | Geography | Closed-set spherical intersection of two geographies. | | [ST\_Intersects](/reference/wherobots-db/geometry-data/geography/functions/ST_Intersects) | Boolean | Test whether two geographies intersect. | | [ST\_Length](/reference/wherobots-db/geometry-data/geography/functions/ST_Length) | Double | Spherical length of a geography, in meters. | | [ST\_MakeLine](/reference/wherobots-db/geometry-data/geography/functions/ST_MakeLine) | Geography | Create a Geography LineString from two supported geographies. | | [ST\_NPoints](/reference/wherobots-db/geometry-data/geography/functions/ST_NPoints) | Integer | Number of points (vertices) in a geography. | | [ST\_NumGeometries](/reference/wherobots-db/geometry-data/geography/functions/ST_NumGeometries) | Integer | Number of sub-geometries in a geography (1 for single geometries). | | [ST\_Within](/reference/wherobots-db/geometry-data/geography/functions/ST_Within) | Boolean | Test whether geography A is fully within geography B. | | [ST\_X](/reference/wherobots-db/geometry-data/geography/functions/ST_X) | Double | Longitude of a point geography. | | [ST\_Y](/reference/wherobots-db/geometry-data/geography/functions/ST_Y) | Double | Latitude of a point geography. |