Longitude is defined as what type of lines on a map?

Longitude is defined as vertical lines on a map that run from the North Pole to the South Pole. These lines help in measuring the angular distance of a location east or west from the Prime Meridian, which is set at 0 degrees longitude.

By convention, longitude lines are drawn vertically because they connect areas of the Earth in a way that reflects the globe's spherical shape. Each degree of longitude becomes narrower as they approach the poles, which further emphasizes their vertical orientation. This vertical arrangement allows for a systematic approach to navigation and charting the Earth, enabling easy calculation of time zones and locations.

In contrast, horizontal lines, which are known as lines of latitude, measure distances north or south of the Equator. Circular lines could imply lines of latitude at different degrees that form circles around the Earth, and diagonal lines do not accurately represent the consistent manner in which longitude is depicted on maps.