# Coordinate System

## Definition

A coordinate system is a standardized method for identifying the location of a point on the earth's surface or in space by using numbers or coordinates. It is a mathematical way of depicting three dimensions (3D) in a two dimensional (2D) format, using three values known as X, Y, and Z. Coordinate systems allow geographical information systems (GIS) to map the world in specific locations, measure distances and areas, and perform spatial analysis.## What is Coordinate System?

Coordinate systems are fundamental to geospatial applications because they enable data from different sources to be integrated and visually represented in layers. There are mainly two types of coordinate systems:- Geographic Coordinate System (GCS): This system uses degrees of longitude and latitude to define locations on the earth's surface. In the GCS, the Earth's surface is represented as a sphere or an ellipsoid.
- Projected Coordinate System (PCS): This system uses linear measurements to define the location, such as feet or meters. The PCS entails mathematical transformations of the Earth's surface to a flat, two-dimensional plane.

It's important to understand that without a coordinate system, it would be impossible to spatially reference physical features or align geographically distributed datasets accurately for a GIS.