Deserts are dry, hot places that receive very little rainfall. They are characterized by large amounts of sand and rocky cliffs, and have few plants. Desert animals and plants have adapted to the harsh environment by storing water in their bodies, burrowing underground to stay cool, and having root systems that allow for quick access to water or reaching deeper water sources. Common desert plants include various cacti like hedgehog, barrel, and saguaro cacti as well as sage brush and prickly pear. Deserts can be found on every continent and cover about 1/8 of the Earth's land surface.