According to estimates, Africa hosts about 2,000 of the approximately 6,000 languages of the world. This number makes the continent one of the hotspots of linguistic diversity. Essential description (i.e. grammars, dictionaries) and documentation (i.e. audio and video speech data and their annotations) is not even available for some of the largest among them. The overwhelming majority of African languages, irrespective of their endangerment status, have received only very little or no linguistic attention to date, despite the fact that many of them are spoken by millions as a first or second language. In addition, a large number of African languages are spoken by small-scale rural communities and can be classified as endangered on diverse grounds, ranging from displacement due to wars or climate change to rural exodus for socioeconomic reasons.