# Difference between CRS (Coordinate Reference System) and SRS (Spatial Reference System)

I could see that CRS and SRS are referred as different components in this question Is WGS84 itself a Coordinate Reference System?

Could anyone please explain whether CRS and SRS are same or different?

## 1 Answer

As of Wikipedia:

A spatial reference system (SRS) or coordinate reference system (CRS)

They are synonyms.

What you see in the linked article is the difference between the reference-ellipsoid which is part of the spatial reference system. In your case `WGS84` is just an ellipsoid, which itself more or less accurately describes the earth. However without any grid there's no way to say where on this sphere a given point is because you don't have any information on where is zero, in which direction is north, how long is a unit. Thus you also need some coordinate system which is the second part of the CRS.

However there exist a bunch of reference-ellipsoids which are almost allways used with only one single coordinate system, like WGS84 is allways used in combination with geographic coordinates having a latitude and a longitude. However you could also express a location based on that ellipsoid in metric coordinates also.

• Thanks for the answer and I have seen the Wikipedia article but was confused by this question gis.stackexchange.com/questions/23690/…. Please correct me if I'm understanding it wrongly. Mar 17, 2016 at 13:29