Desert region lies in both Tropical and Temperate regions. In Tropical region it lies on the both sides of equator between 15° to 25° latitudes in the west of the continents. This region includes the great Sahara desert which stretches across nine countries including Mauritania, Mali, Algeria, Chad and Sudan, The Kalhari desert in Angola (Africa) Rajistan desert in Inida, Thal desert in Pakistan, Iranian and Arabian deserts, Mangolia and Gobi desert China in Asia along with deserts of Peru and Chile in South America and central Australia.