A grid reference system, also known as grid reference or grid system, is a geographic coordinate system that defines locations in maps using Cartesian coordinates based on a particular map projection. Grid lines on maps illustrate the underlying coordinate system.

An area reference is a general location indicated on a map, such as a city or region, while a grid reference is a specific point identified by intersecting lines on a grid system, such as latitude and longitude coordinates or a military grid reference system (MGRS). Essentially, an area reference gives a broader location, while a grid reference pinpoints a precise position within that area.

1,000 meters

NovaNet - Military Grid Reference System