Geographic coordinate system
A geographical coordinate system is a
A full circle can be divided into 360 degrees (or 360°); this was first done by the Babylonians; Ancient Greeks, like
Today, degrees are divided further. There are minutes, and seconds; 1 minute (or 1') in this context is 1/60 of a degree; 1 second (or 1") is 1/60 of a minute.
The first concept needed is called latitude (Lat, or the Greek symbol "phi", ). For it, the Earth is cut up into 180 circles, from the
The other concept is called longitude (Long, or the Greek symbol "lambda", ), sometimes referred to as "meridian". The 0° longitude line (or zero meridian) goes through the
The third number is the height, altitude, or depth. This is given with respect to some fixed (usually easily calculable point). One of these is called