Languages indigenous to Africa that belong to the Nilo-Saharan , Khoisan , and Afro-Asiatic language phyla.
Africa is the most polyglot continent; estimates of the number of African languages range from 1,000 to more than 1,500. Many have numerous dialects. Distinctions in tone play a significant role in nearly all sub-Saharan languages. Contact between people who do not speak the same language has necessitated the development of lingua franca s such as Swahili in East Africa, Lingala in the Congo River basin (see {{link=Bantu languages">Bantu languages ), Sango in the Central African Republic (see Adamawa-Ubangi languages ), and Arabic across much of the Sahel .