Africa, the planet's
2nd largest continent and the second most-populous continent (after
Asia) includes (53) individual countries, as well as Western Sahara, a
member state of the African Union whose statehood is disputed by
Morocco.
With just over a billion people (a 2009 estimate) it accounts for just
over 14% of the world's human population. It also contains the Nile
River system, the world's longest, and the massive Sahara Desert, the
world's largest.
Africa 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 straddles the equator and encompasses numerous climate
areas, and is the only continent to stretch from the northern temperate
to southern temperate zones.
Africa, particularly central eastern Africa, is widely thought (by
science) to be the origin of humans as evidenced by the discovery of the
earliest hominids and their ancestors.