They are important for tracking and mapping points and places.
latitude?
lines of latitude
Each 'meridian' is a line of constant longitude.
Latitude.
Every meridian of longitude is perpendicular to every parallel of latitude, and every parallel of latitude is perpendicular to every meridian of longitude.
The lines that intercept latitude lines are lines of longitude.
Latitude and longitude
Lines of Longitude
Longitude lines go vertically and latitude lines go horizontally.
Every parallel of latitude crosses every meridian of longitude.
Lines of latitude and longitude allows any position on the Earth to be plotted.
Latitude lines run parallel to the equator and measure a location's distance north or south of the equator, while longitude lines run perpendicular to the equator and measure a location's distance east or west of the prime meridian. Latitude lines are represented by horizontal lines on maps, while longitude lines are represented by vertical lines.