Africa is the second largest continent, with major rivers including the Nile, Zaire, Zambezi, and Niger. It is located between the Atlantic Ocean to the west and the Indian Ocean to the east, with the Sahara desert covering much of the northern region. The continent contains diverse ecosystems like rainforests along the equator, savannas with grasslands and scattered trees covering around half the land, and deserts such as the Sahara making up 40% of the area.