Flickering heat or icy cold: deserts are habitats of extremes. Only a few plants and animals survive in the dryness. Spiky cacti can store water. Beetles and geckos capture fog to drink it. And for centuries, people have traveled from oasis to oasis with their desert ship, the camel. WHAT IS WHAT reports on the types of deserts on our planet, survival without water, nomads and blue riders, traders and explorers, natural resources, and desert metropolises.