Talcott Parsons universalistic -achievement pattern variable is central to the industrial society.
Touraine described the Post Industrial Society as technocratic society.
Maclver emphasized that urban life has fostered the individualization of women.
Spengler has described cities as sinks of civilization.
E.E Muntz has classified cities on the basis of their principal activities.
Ullman has defined the city as a relatively large, dense and permanent settlement of socially heterogeneous individuals.
Redfield has remarked that urban groups have a reputation for namelessness.
Christaller is associated with the central place theory.

Burgess put forward the concentric zone hypothesis on a diagrammatic study of Chicago.

The town encourages associative individualism.
Commuter's zone is also called bedroom community.
Hyat has emphasized the importance of transportation routes in the expansion of a city.
The compositional theory is based on rural-urban differences.
The culture of poverty refers to slums.
Migrants from rural to urban areas adjust more smoothly to city life it they maintain kinship ties.
Oscar Lewis has given the concept of culture of poverty.
Wirth has remarked that urbanism is a way of life whereas urbanization is a process.
Maclver says that cities grow wherever a society or a group within it gains control over resources greater than are necessary for the mere sustenance of life.
Robert Redfield has given four characteristics of little community. These are- distinctiveness, smallness, homogeneity and self-sufficiency.
Ravenstein has developed the theory of step-migration.
Marx perceived the petty bourgeois to be a transitional class.
Weber believed greater bureaucratization would lead to greater alienation..
Singer and Marriot hold the social structure of civilization to operate at the levels of peasants and industrialists.