Chimpanzee, sometimes colloquially chimp, is the common name for the two extant species of ape in the genus Pan. The Congo River forms the boundary between the native habitat of the two species, the common chimpanzee (Pan troglodytes), the more numerous and better known that lives primarily in West and Central Africa, and the bonobo (Pan paniscus), also known as the "pygmy chimpanzee or Bonzi chimpanzee", found in the forests of the Democratic Republic of the Congo.
Chimpanzees are members of the Hominidae family, along with gorillas, humans, and orangutans. Chimpanzees split from human evolution about 6 million years ago and thus the two chimpanzee species are the closest living relatives to humans, all being members of the Hominini tribe (along with extinct species of Hominina subtribe). Chimpanzees are the only known members of the Panina subtribe. The two Pan species split only about one million years ago.