A cartogram is a map on which mainly the quantitative aspects of the phenomena to be studied are displayed. It is a special example of a statistical map.
Such maps are scrambled based on data. This distortion can produce a bizarre map image. The deformation is done by applying a homeomorphism to the original geographic map. This can be imagined as a map drawn on a rubber sheet that can be stretched or contracted at will, but not cut up. Homeomorphism ensures the continuity of the map: areas that adjoin each other do this even after deformation. But the size of the areas is now not proportional to their surface area, but to another attribute, for example the number of inhabitants or the gross national product.
