With the demographic explosion of young people in major African cities, we are witnessing the emergence of youth languages and new speech forms. In search of well-being, these young people, plagued by poverty, social injustice, unemployment and idleness, invent linguistic codes that allow them to find themselves. The linguistic and sociolinguistic description of these youth languages is the object of this volume. The contributions inform on the statutes and functions of the youth languages of Africa, their forms and structures, their representations, and envisage perspectives and prospective didactics.