The document is an International Encyclopedia of the Social Sciences about conditions and causes of slums. Slums are squalid sections of a city or town, areas in which most inhabitants are in or near poverty, stores and residences are cheap and dilapidated, and streets are narrow and blighted. Slums have been created in various locations; where they arise depends upon political and economic conditions in a community. The slums housed the lowest paid workers not far from the center of the city, close to factories gates. To this day, slums  cities are typically located in areas, though often the factories have closed down. In other cities, where central areas retained high land and rent value, large public housing projects were built on the outskirts and slums developed and still exist on peripheral areas . Perhaps the world’s largest slum (Dharavi) is on the northern edge of the city of  Mumbai.