The Algerian Sahara has every kind of desert you can imagine. There are huge seas of golden dunes called 'erg' - the famous Grand Erg Oriental and Grand Erg Occidental. There are flat stony plains called 'reg', and there are dry rocky plateaus called 'hamada'. From a plane, the colours range from pale yellow to deep orange to almost black.
Even though it looks empty, the Sahara has people, towns and oases. An oasis is a place where water comes to the surface and palm trees grow - a green island in the middle of all that sand. The Algerian town of Timimoun is famous as the 'Red Oasis' because of its red mud buildings and the date palms that surround it.
The desert is full of surprises. Temperatures can be 45掳C in the day and drop to near freezing at night - because dry air doesn't hold heat. Storms of sand can fly through the sky for days. After a rare rainstorm, tiny green plants pop up out of the sand almost overnight.
Lots of children in southern Algeria grow up knowing the desert the way other children know forests or beaches. They know which dunes the wind shifts, where to find a date palm and how to spot a fennec fox's tracks in the sand.