The Sahara is a sandy desert with giant sand dunes. It covers over 3 million square miles of Africa. Other major deserts include the Arabian Desert in the Middle East, the Gobi Desert in Northern China and Mongolia, and the Kalahari Desert in Africa. Go here to learn more about the World's deserts.he Sahara is a sandy desert with giant sand dunes. It covers over 3 million square miles of Africa. Other major deserts include the Arabian Desert in the Middle East, the Gobi Desert in Northern China and Mongolia, and the Kalahari Desert in Africa. Go here to learn more about the World's deserts.
Addiction is a persistent, compulsive dependence on a behavior or substance. The term has been partially replaced by the word dependence for substance abuse. Addiction has been extended, however, to include mood-altering behaviors or activities.
View full size image. Addiction is a chronic brain disorder and not simply a behavior problem involving alcohol, drugs, gambling or sex, experts contend in a new definition of addiction, one that is not solely related to problematic substance abuse.t's a brain problem whose behaviors manifest in all these other areas, said Dr. Michael Miller, past president of ASAM who oversaw the development of the new definition. Many behaviors driven by addiction are real problems and sometimes criminal acts. But the disease is about brains, not drugs.