Title: What are grid and coordinates systems
Headings: Map Reading – What are grid and coordinates systems?
Map Reading – What are grid and coordinates systems?
Coordinate Systems
Geographic Coordinate Systems (GCS)
Universal Transverse Mercator (UTM)
A couple more points
Wrap up

Content: The one most commonly used is the WGS84 (World Geodetic System, updated at 1984), while in the USA you can find NAD83 (North American Datum 1983) and in the UK, OSGB36 (Ordinance Survey of Great Britain 1936). All three GCSs are very similar, so not much of a problem there. The data are just a reference point to keep an eye on if you are in a less surveyed area. From all this you can see that the GCS is a very complicated system, so luckily for us, most of the mapping on the planet moved to a much simpler system, UTM: Universal Transverse Mercator (UTM)
The UTM system is based on a basic concept of meractor projection: ‘ pseudocylindrical’ conformal projection (big words for preserving it shape). The UTM is a projection of earth’s sphere using the poles to create a flat representation of that sphere, meaning, the maps you see everywhere. This is done by swathing (creating over-lapping layers) – areas around the equator are over-lapped, resulting in zone boundaries overlapping in some places. This is used in order to avoid curvature in the longitude strips of each zone (which would make it impossible to show on a flat map!). By creating a flat representation, the world can be divided into rectangles (called UTM zones) that are easy to find and use on maps.