Choropleth Map

http://my.ilstu.edu/~jrcarter/Geo204/Choro/

This is an example of a Choropleth map. This map type shows areal data that is areally averaged, meaning the information data is averaged across an area, in this case it is averaged for an entire state. This map shows us the number of males for every 100 females in every state, and the variation is shown via color shading.