Classed Choropleth Map

http://go.owu.edu/~jbkrygie/krygier_html/geog_353/geog_353_lo/geog_353_lo07.html

Classed choropleth maps have all the characteristics of a choropleth map, and are considered "classed" because they have a key that tells you what the variable being shown is. Most choropleth maps are classed  because of how difficult it would be to notice what an unclassed map is showing you. Both maps above are examples of classed maps because of how they show what the variable is by the key.