Choropleth Map

A Choropleth Map is a map that has ceretain areas or regions shaded in with a particular color that is proportional to the entire population being studied.  For example age/population density or presidential election/voter turnout.  These maps help distinguish more than just one fact by viewing one key.  For example, after viewing the key for this particular presidential election map, you will then know by glancing  at any state: who the state elected as president, how much the margin of victory was(aproximately), and aproximately what the voter turnout was.
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