The earths zero of longitude.
Prime meridian
An imaginary line, that is an equal distance from both poles.
Equator
Conveys a theme; tries to prove a point
Thematic
Displays borders/ boundaries and country names
Political
Displays resources
Economic
Displays climate/ temperature
Climate
Displays types of landforms/ physical features
Physical
Is used to specify the precise location of features on earth.
Latitude and longitude.