There are 360 degrees of longitude (+180° eastward and −180° westward.). The longitude line of 0 degrees is known as the Prime Meridian and it divides the world into the Eastern Hemisphere and the Western Hemisphere.
Longitude (meridians) are the vertical lines on a map. They all converge at the two poles (North Pole and South Pole), and 0° longitude is located at Greenwich, England (0°). In the east hemisphere, the longitude ranges from 0° to 180°E, and in the west hemisphere,the longitude ranges from 0° to 180°W.
