The San People, also known as the Bushmen,are members of various Khoesān-speaking indigenous hunter-gatherer groups that are the first nations of Southern Africa, and whose territories span Botswana, Namibia, Angola, Zambia, Zimbabwe, Lesotho and South Africa. The ancestors of the hunter-gatherer Sān are thought to have been the first inhabitants of what is now Botswana and South Africa. Sān were traditionally semi-nomadic, moving seasonally within certain defined areas based on the availability of resources such as water, game animals, and edible plants. From the 1950s through to the 1990s, Sān communities switched to farming because of government-mandated modernisation programs. Total population is estimated to be 90,000; 27,000 of them in Namibia.