A good map is a map that clearly communicates its message to the reader. It should be easy to interpret map elements based on the symbology and graphics used, get oriented, and determine things such as distances and directions. Obviously, good cartography is critical; however, professionally produced maps typically include several elements outside of the actual mapped area, such as a scale bar, a legend and a north arrow, and for good reason. A scale indicates the relationship between a defined distance on the ground and the corresponding measurement on the map. Adding a scale bar to a map will make all measurements much easier. A north arrow aids in easy orientation. Without that, it would be often impossible to judge directions, for example where the southern exposure of a building is. A legend or a key is a guide to how features on the earth are symbolized on the map. For example, streets are often symbolized by lines of varying thickness. Including these elements in your maps will increase the effectiveness and functionality of the final output.