This lecture covers the characteristics of informal settlements, focusing on the vulnerable populations living in precarious conditions with limited access to basic infrastructure. It discusses the physical and legal precariousness of their living conditions, the risks associated with their location, and the lack of integration within the city. The presentation also includes a case study of Pikine Irrégulier Sud in Dakar and highlights initiatives such as MOOCs for Africa and partnerships for sustainable development in higher education in Africa.