Africa is the world's second-largest and second-most-populous continent (the first being Asia). At about 30.3 million km (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20.4% of its total land area. With /1e9 round 1 billion people as of , it accounts for about 16% of the world's human population. The continent is surrounded by the Mediterranean Sea to the north, both the Suez Canal and the Red Sea along the Sinai Peninsula to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagos. It contains 54 fully recognised sovereign states (countries), nine territories and two "de facto" independent states with limited or no recognition. 

Africa's average population is the youngest amongst all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Algeria is Africa's largest country by area, and Nigeria is its largest by population. Africa, particularly central Eastern Africa, is widely accepted as the place of origin of humans and the Hominidae clade (great apes), as evidenced by the discovery of the earliest hominids and their ancestors, as well as later ones that have been dated to around seven million years ago, including "Sahelanthropus tchadensis", "Australopithecus africanus", "A. afarensis", "Homo erectus", "H. habilis" and "H. ergaster"—with the earliest "Homo sapiens" (modern human) found in Ethiopia being dated to circa 200,000 years ago. Africa straddles the equator and encompasses numerous climate areas; it is the only continent to stretch from the northern temperate to southern temperate zones.
By population?
 Nigeria is its largest by population