Main purpose is to communicate variation in spatial density. Technique involves the selection of an appropriate point symbol (dot) to represent each discrete element of a geographically distributed phenomenon. The symbol form does not change, but its number changes from place to place proportion to the number of objects being represented. Dot Map
Choropleth Map Put data into a spatial format and are useful for determining demographic data, such as infant mortality rates, by assigning colors or patterns.
Graduated Circles Map Type of quantitative thematic map in which point data are represented by a circle whose size varies with the data values.