what is a legend on a map

A legend on a map is a description, explanation, or table of symbols printed on a map or chart to permit a better understanding or interpretation of it. It displays the meaning of the symbols, colors, and styles used to represent geographic data on the map. A map legend usually contains information on the map scale as well. It includes symbols and colors to represent various objects, but also includes other important information such as the scale of the map. The purpose of the legend or key is to give the reader the information needed to interpret the symbols on the map correctly. The legend consists of examples of the symbols on the map with labels containing explanatory text, and often, legend patches are points, straight lines, rectangles, or color ramps that match the map symbols. Without a legend, it would be difficult to understand the meaning of the symbols on a map, especially if there are many different symbols used.