The design of thematic maps follows four basic principles: location principle, chart principle, image-static principle and the pictorial principle. The most important elements of the map form the thematic information. This originates depending on the topic from different sources. If necessary, the data have to be collected. In addition, the topic is supported by a base map, which has, among others, the task to place the thematic information in a geospatial context. The information density of the base map depends on the topic of the map.