what is a map key
What is a map key? A map key is a list of words or phrases or colors -- usually within a box in the corner of the map -- that usually explains the symbols that that are found on the map itself.ou look at the colors and if a color is on the map and on the  scale/key, it is the same then they mean the same thing for example  if blue means 50 and green means 65 and â¦ the whole map is blue the  whole area is 50 degrees. + 1 other found this useful. Bronte Veitch.