The San Bushmen call the Central Kalahari "The Land God Made in Anger," and most of the time the description holds good.
It's really hot. It's really dry. It's really inhospitable. There's no permanent water. No lakes. No rivers. If you don't know how to change a tire, or forget your water, the Central Kalahari could, very conceivably, mummify you. From time to time, however, the Almighty mellows, cuts what the Boers call "the thirstland" some slack and sends a little rain over, with sensational results.
Before getting into that, though, a little background. First, although the Kalahari is often referred to as a "desert," it isn't. Not technically. To officially qualify for desert status, land must receive less than 25 mm of rain per annum, and overall the Kalahari gets a great deal more. Even the driest bits get 100 mm or so.