Probably you too have been making maps in school and have had the fun of coloring them. I live at Mohonk Lake, New York. If you wanted to visit me, to see some of the interesting old maps I have collected, you would probably use a map to see where I am. When you come to use maps along the highways, signs are needed in addition. They are of several kinds.
Signs are an important aid to travel.
They are keys for fitting what is on the ground with what is on the map. When you travel on water in motor boats and sail boats you should have charts to travel up rivers and along coasts. These are both really kinds of maps. While you are traveling a route between two places you are pretty apt to find some rough spots. There may be construction going on, or a detour, or snow and ice in winter.