Title: Grid reference system - Wikipedia
Headings: Grid reference system
Grid reference system
Contents
Grid coordinates
Notation and conventions
Grid north
Types
See also
References

Content: It is not to be confused with East north up. 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. Such coordinate lines are numbered to provide a unique reference to each location on the map. Grid coordinates are normally eastings and northings. Contents
1 Grid coordinates
1.1 Notation and conventions
2 Grid north
3 Types
4 See also
5 References
Grid coordinates
UTM zones on an equirectangular world map with irregular zones in red
Easting and northing are geographic Cartesian coordinates for a point. Easting is the eastward -measured distance (or the x - coordinate) and northing is the northward -measured distance (or the y -coordinate). When using common projections such as the transverse Mercator projection, these are distances projected on an imaginary surface similar to a bent sheet of paper, and are not the same as distances measured on the curved surface of the Earth . Easting and northing coordinates are commonly measured in metres from the axes of some horizontal datum. However, other units (e.g., survey feet) are also used.