What does the term 'scale' refer to in mapping?

The term 'scale' in mapping specifically refers to the ratio of map distance to Earth distance. This concept is essential for understanding how distance on a map translates to actual distance in the real world. For example, if a map has a scale of 1:100,000, this means that 1 unit of measurement on the map (like an inch or a centimeter) corresponds to 100,000 of the same units in reality. This ratio helps users accurately interpret the size and distance of geographic features and allows for proper navigation and analysis based on the map's representation.

In addition to this, understanding scale is crucial when comparing maps at different scales, as larger scale maps will show more detail for a smaller area, whereas smaller scale maps show a broader area with less detail. This concept plays a significant role in cartography and GIS, affecting how data is visualized and analyzed. The other aspects mentioned in the other options, such as the representation of three-dimensional objects or the type of projected coordinate system, do not directly pertain to the definition of scale in mapping.