Suburbanisation is a term used by many to describe the current social urban dynamic operating within many parts of the developed world and is related to the phenomenon of urban sprawl. Many residents of larger cities no longer live and work in the same urban area, choosing instead to live in suburbs and commute to work in other areas. This has set some urban areas of developed countries like the United States apart from many other countries where the majority of people live in urban areas with higher population densities. Urban sprawl (also called suburban sprawl) is a pejorative term for the expansive, often explosive and sometimes reckless, growth of a metropolitan area, traditionally suburbs (or exurbs) over a large area. ... It has been suggested that Suburbia be merged into this article or section. ...

Suburbanization in the United States really began after the Civil War, when the cottage was touted as the cure for modern society's problems. By 1900, suburbs were near every major US city, and the city had become primarily a place of work, rather than living. Those who lived in the city were increasingly poor, as the wealthy, who had lived there not too long ago, moved to these suburbs. This has resulted in the suburb’s association with those who are well off, and the city's association with poverty. The American Civil War (1861–1865) was fought in North America within the United States of America, between twenty-three mostly northern states of the Union and the Confederate States of America, a coalition of eleven southern states that declared their independence and claimed the right of secession from the... 1900 is a common year starting on Monday. ...

Racial prejudice also played a role in American suburbanization. During World War I, the massive migration of African-Americans from the South, and later the 1954 Supreme Court ruling outlawing school segregation, resulted in an even greater residential shift toward suburban areas. The cities became seen as dangerous, crime infested areas, while the suburbs were seen as family safe places. This view runs counter to much of the world, where slums mostly exist outside the city, rather than within. This social trend is known in some parts of the world as white flight 1954 (MCMLIV) was a common year starting on Friday of the Gregorian calendar. ... The supreme court in some countries, provinces, and states, is the highest court in that jurisdiction and functions as a court of last resort whose rulings cannot be appealed. ... White flight is a colloquial term for the demographic trend of upper and middle class white people moving away from (predominantly non-white) inner cities, finding new homes in nearby suburbs or even moving to new locales entirely, e. ...

The automobile and other transportation inventions also helped spur the movement forward by enabling people to live even farther away from their place of work. Suburbanization is now mostly to blame for the growing traffic problems plaguing some countries metropolitan areas. A small variety of cars, the most popular kind of automobile. ...

By 1990, it was estimated that more than 45% of the US population lived in suburban areas. This massive shift from urban to suburban living has made the United States the world's first suburban nation.