Thematic maps usually focus on just one theme with only minimal reference information to provide the map reader with geographic context. There are many examples of thematic maps, including weather maps, population density maps, voting maps, soils maps, and more. These are some characteristics of thematic maps:
The goal of a thematic map is to draw the reader's attention to the significance in the distribution of one or few geographic phenomena. The map maker must therefore direct the reader's attention using carefully considered symbology and labeling. This task becomes substantially more difficult if more than one theme of information is included on a thematic map, e.g., a bi- or multi-variate map.
The emphasis of thematic maps is on the geographic pattern of the feature attributes. One challenge in making thematic maps is to figure out which features to include as the minimal required locational reference information (that is, what to exclude from the map.) In contrast, for general reference maps, the challenge is to figure out which classes of features are of greatest interest and use to a wide range of users (that is, what to include on the map.)