Permafrost regions are areas of the world where the ground is permanently frozen. These regions are typically found in the Arctic and Antarctic, and are characterized by extremely cold temperatures and low precipitation. The term 'tundras' is used to describe these regions, as it refers to a type of biome that is characterized by low temperatures, low precipitation, and a lack of trees. Tundras are often covered in snow and ice for much of the year, making them inhospitable to most forms of life.