- Earth is divided into a grid of vertical parallels(lines) of longitude and horizontal meridians(lines) of latitude.
- The meridians of longitude are measured in degrees up to 180 starting at the prime meridian.
- The parallels of latitude are measured in degrees up to 90 starting at the equator.
6.2.4 Define and identify, on a diagram of the earth:
(a) axis and direction of rotation;
(b) geographic and magnetic poles;
(c) the equator;
(d) parallels of latitude;
(e) meridians of longitude;
(f) Greenwich (Prime) Meridian;