Urbanization

The New York City skyline at night is shown here.
The lights of New York City are an iconic image of city life. (Photo courtesy of Or Hiltch/flickr)

Urbanization is the study of the social, political, and economic relationships in cities, and someone specializing in urban sociology studies those relationships. In some ways, cities can be microcosms of universal human behavior, while in others they provide a unique environment that yields its own brand of human behavior. There is no strict dividing line between rural and urban; rather, there is a continuum where one bleeds into the other. However, once a geographically concentrated population has reached approximately 100,000 people, it typically behaves like a city regardless of what its designation might be.