Which concept involves using colors and symbols to enhance map readability?

The concept of using colors and symbols to enhance map readability is best represented by visual contrast. Visual contrast refers to the differential visual properties, such as color, brightness, and saturation, that allow various elements on a map to stand out from one another. By employing contrasting colors and symbols, mapmakers can create a visual hierarchy, guiding the viewer's attention to important features or information on the map. This enhances the overall readability of the map, allowing users to interpret the data more effectively.

Utilizing visual contrast ensures that different elements do not blend together, which could lead to confusion or misinterpretation. For example, using light colors for less important features and bold, dark colors for key aspects draws the viewer's eye and helps convey the significance of what they are looking at in a clear manner.

While hue refers specifically to a color's dominant wavelength, shape pertains to the geometric or physical form of symbols on a map, and pattern indicates a repeated decorative design, these elements play a role in visual design but do not directly address the primary goal of enhancing map readability through contrasting features in the same way that visual contrast does.