Thematic Map

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Thematic maps show the distribution of a single attribute/characteristic or the relationship between several attributes.  It is up to the map maker to make sure that the correct use of these maps are portrayed. 
Geographic patterns in statistical data, such as population or median income, displayed as color-coded areas on a map are examples.  The above portrays the Median Age of the Total Population of the United States between 2005-2009.