Applying color to maps is a little more complicated than just picking a few things off the wheel. We have physical and psychological interactions with color, and it's important to understand the basics of these before we start madly coloring in shapes.
Color theory is the formalized examination of the blending of colors and how we perceive them. Early 19th century works by Goethe and others documented such phenomena as complementary colors and color afterimages. Evolution in science led to a better understanding of the visual perception of color, and technological advances in chemistry made color printing and photography more feasible, which led to the development of the RGB and CMYK models. From these, and later work on the subject, we came to understand how colors interact with each other, and how the brain interprets those interactions.
To simplify for our purposes, let's look at three basic principles of color:
- Colors interact with their environment; namely...