Unclassed Choropleth Maps

In a conventional Unclassed Choropleth map, a continous ramp of shading or color intensity is used to illustrate a scale of data. The lowest and highest color intensities are assigned to the lowest and highest values respectively. A distinctive feature of unclassed choropleth maps is that each unique value has a unique shading of color. As you can see above, the scale for an unclassed choropleth map is a continuous grading of color, with each color representing a specific value.

http://www.princeton.edu/~rvdb/JAVA/election2004/purple_america_2004_small.gif