Abstract: A Cartogram is a visualization method to highlight one or more given attributes of geographic features through simplification or distortion of a map. In recent years, it has become more and more popular in the cartographic research area. But most of research results are scattered in different scientific fields, such as statistics, computer graphics and cartography. There are very few systematic summaries of Cartograms. Therefore, it is necessary to review all the researches on Cartograms. In this paper, we first introduce the concepts, classifications and evolution of Cartograms. Then, we present automatic construction methods of line Cartograms and area Cartograms according to different types. Afterwards, we summarize evaluation methods of Cartograms and provide five evaluation indexes of Cartograms. Finally, we propose challenges and future research directions of Cartograms.