Geographic coordinate system

A system for locating positions on Earth with angular coordinates, usually latitude and longitude, defined relative to a geodetic datum.

Latitude: An angular coordinate measuring a position north or south of the equator. It supplies the north–south component of the system’s usual coordinate pair.
Geodetic coordinates: Coordinates that specify latitude, longitude, and usually height relative to a reference ellipsoid. They are the standard angular form used to express positions in this system.
Global Positioning System: A satellite navigation system that estimates position and time using signals from orbiting satellites. GPS receivers commonly report positions as latitude and longitude.
Projected coordinate system: A planar coordinate system that locates positions with linear units after a map projection. It replaces angular latitude and longitude with map-plane coordinates.
Longitude: An angular coordinate measuring a position east or west of a reference meridian. It supplies the east–west component of the system’s usual coordinate pair.
Coordinate reference system: A framework defining how coordinates relate to locations on Earth. It is the broader framework that identifies a geographic system’s datum and coordinate conventions.
Geographic information system: A system for storing, analyzing, and displaying data linked to locations. GIS layers rely on geographic coordinates to align features across datasets.
Cartesian coordinate system: A coordinate system that locates points using distances along perpendicular axes. Its linear axes differ from the angular coordinates used for geographic positions.
Geodetic datum: A reference framework specifying an Earth model, its orientation, and the origin used for geographic coordinates. It anchors coordinates to a defined Earth model rather than an abstract globe.
Map projection: A mathematical transformation that represents positions on a curved surface on a flat map. It converts geographic coordinates into planar coordinates for many maps.

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