There are several other small families and language isolates, as well as languages that have yet to be classified. In addition, Africa has a wide variety of sign languages, many of which are language isolates (see below).
The total number of languages natively spoken in Africa is variously estimated (depending on the delineation of language vs. dialect) at between 1,250 and 2,100, and by some counts at "over 3,000", Nigeria alone has over 500 languages (according to the count of SIL Ethnologue), one of the greatest concentrations of linguistic diversity in the world. However, "One of the notable differences between Africa and most other linguistic areas is its relative uniformity. With few exceptions, all of Africa’s languages have been gathered into four major phyla."
Around a hundred languages are widely used for inter-ethnic communication. Arabic, Somali, Berber, Amharic, Oromo, Igbo, Swahili, Hausa, Manding, Fulani and Yoruba are spoken by tens of millions of people. Twelve dialect clusters (which may group up to a hundred linguistic varieties) are spoken by 75 percent, and fifteen by 85 percent, of Africans as a first or additional language. Although many mid-sized languages are used on the radio, in newspapers and in primary-school education, and some of the larger ones are considered national languages, only a few are official at the national level. The African Union declared 2006 the "Year of African Languages".
Most languages spoken in Africa belong to one of three large language families: Afroasiatic, Nilo-Saharan and Niger–Congo. Another hundred belong to small families such as Ubangian (sometimes grouped within Niger-Congo) and the various families called Khoisan, or the Indo-European and Austronesian language families mainly spoken outside Africa; the presence of the latter two dates to 2,600 and 1,500 years ago, respectively. In addition, the languages of Africa languages include several unclassified languages and sign languages.
The earliest Afroasiatic languages are associated with the Capsian culture, the Nilo-Saharan languages are linked with the Khartoum Mesolithic/Neolithic, the Niger-Congo languages are correlated with the west and central African hoe-based farming traditions and the Khoisan languages are matched with the south and southeastern Wilton industries. More broadly, the Afroasiatic family is tentatively grouped within the Nostratic superfamily, and the Nilo-Saharan and Niger-Congo phyla form the Niger-Saharan macrophylum.