The planet surface is covered by endless dunes. There is no vegetation, and no terrestrial source of water has been found. Miles of barren deserts hold nothing more than basins, dunes, and occassional rocky outcroppings.
Two known species represent the native life-forms of the planet: Fremen and Sand Worms. Legends suggest the Fremen are descended from survivors of an ancient interstellar shipwreck. Long overlooked by the rest of the Imperium and considered backward savages, in reality they are an extremely hardy people and exist in large numbers. The Fremen as humans in extremis, over time they adapt their culture and way of life to survive and thrive in the incredibly harsh conditions of desert. The Fremen are distinguished by their fierce fighting abilities and adeptness at survival in these conditions. With water such a rare commodity on the planet, their culture revolves around its preservation and conservation.
The Sand Worms (known among Fremen as Shai Hulud) travel easily beneath the surface of the sand. A possible component of the Melange complex, these hideous creatures have gained a justified reputation for attacking anything that moves on the sand's surface, and will devour either humans or their vehicles when the opportunity arises, in that vast desert the only secure place is the solid rock.
Background picture by Michael "Mike" L. Baird, licensed under the Creative Commons Attribution 2.0 Generic license. « Less