They are used to help locate and describe specific areas. The parallel lines of latitude are horizontal, running from east to west. Unlike lines of latitude, which become progressively shorter as they near the poles, all of the lines of longitude are the same length.
Longitudinal lines run from north to south, each individual vertical line intersecting both poles.
The prime meridian is an arbitrarily selected line from which all of the others are measured. The students will discuss and compare the time zones of the world. Review the four hemispheres. Point out on a globe where each hemisphere is located. Review line of latitude with the students.