Lines of longitude are also known as meridians. Lines of longitude and latitude create a grid pattern on the globe for navigation. The Earth is split into 360 lines of longitude. The Prime Meridian runs through Greenwich, England, while the equator serves as the zeroth pace for latitude.
Lines of longitude are typically expressed as the vertical lines on a globe or a map, all crossing through the north and south poles of the planet. Meridian distance is counted in degrees, minutes and seconds from east to west. The International Date Line is 180 degrees east or west from the Greenwich Prime Meridian.