mapmakers may also use colors that are related to what they are mapping. for example, when mapping where it rains more or less, they may use different shades of blue. for a map of wildfires, they may use yellows, reds, and oranges. carefully choosing colors is important so the map is easy to read and understand. also, the mapmaker must take into account that many people have impaired color vision, and colors must be used such that these readers can see their differences.