These top two photos are from Kibera, Kenya's largest slum (located in Nairobi). The people live in houses made of mud and/or iron sheets.
The other three photos are from Kayole, one of Nairobi's "estates". By Kenyan standards, it's not a slum. Most of the people in these types of neighborhoods live in "flats" (apartments). The buildings are constructed with stones (similar in size and shape to a cement block) and cement. Many of the flats are only 10x10 feet square. All flats on each floor share a toilet, sink, and "bath" room.