Grid reference

Grid references define locations in maps using Cartesian coordinates. Grid lines on maps define the coordinate system, and are numbered to provide a unique reference to each location on the map. This reference is normally based on projected eastings and northings. Grid references define locations in maps using Cartesian coordinates. Grid lines on maps define the coordinate system, and are numbered to provide a unique reference to each location on the map. This reference is normally based on projected eastings and northings.