Suburbs are commonly defined as the residential areas which surround the central area of the urban area of a town or city. In the United States, suburbs have a prevalence of usually detached  single-family homes. . Some suburbs have a degree of political autonomy, and most have lower population density than inner city neighborhoods. Modern suburbs have grown in the 20th century as a result of improved road and rail transport and an increase in commuting. Suburbs tend to proliferate around cities which ideally have an abundance of adjacent flat land . Any particular suburban area is referred to as a suburb, while suburban areas on the whole are referred to as the suburbs or suburbia and the demonym being a suburbanite.
The word is derived from the Old French subburbe and ultimately from the Latin suburbium, formed from sub, meaning "under", and urbs, meaning "city". In Rome, important people tended to live within the city wall on one of the seven roman hills, while the lower classes often lived outside of the walls and at the foot of the hills. "Under" in later usage sometimes referred variously to lesser wealth, political power, population, or population density. The first recorded usage, according to the Oxford English Dictionary, comes from Wycliffe in 1380, where the form subarbis is used.
In the United States, Canada, and most of Western Europe the word suburb usually refers to a separate municipality, borough, or unincorporated area outside a central town or city. This definition is evident in the title of David Rusk's book Cities Without Suburbs (ISBN 0-943875-73-0), which promotes metropolitan government. U.S. colloquial usage sometimes shortens the term to burb, and "the Burbs" first appeared as a term for the suburbs of Chicago.
This division is not as prevalent in Ireland, the United Kingdom, Australia and New Zealand. In Ireland and the United Kingdom, suburb merely refers to residential neighborhoods outside of the city centre whether they lie in a separate municipality or not. In Australia and New Zealand, suburbs have become formalized as geographic subdivisions of a city and are used by postal services in addressing. In rural areas of Australia their equivalent are called localities (see suburbs and localities). In Australia, the terms inner suburb and outer suburb are used to differentiate between the higher-density suburbs with close proximity to the city center, and the lower-density suburbs on the outskirts of the urban area. Inner suburbs, such as Te Aro in Wellington, Prahran in Melbourne and Ultimo in Sydney, are usually characterised by higher density apartment housing and greater integration between commercial and residential areas.
Prior to the 19th century, suburb often correlated with the outlying areas of cities where work was most inaccessible; implicitly, where the poorest people had to live. Charles Dickens used the word this way, albeit not exclusively, in his descriptions of contemporary London. The modern American usage of the term came about during the course of the 19th century, as improvements in transportation and sanitation made it possible for wealthy developments to exist on the outskirts of cities. The Australian and New Zealand usage came about as originally outer areas were quickly surrounded in fast-growing cities, but retained the appellation "suburb" and it was eventually applied to the original core as well.
The growth of suburbs was facilitated by the development of zoning laws, redlining and various innovations in transport. After World War II availability of FHA loans stimulated a housing boom in American suburbs. In the older cities of the northeast U.S., streetcar suburbs originally developed along train or trolley lines that could shuttle workers into and out of city centers where the jobs were located. This practice gave rise to the term bedroom community, meaning that most daytime business activity took place in the city, with the working population leaving the city at night for the purpose of going home to sleep.
The growth in the use of trains, and later automobiles and highways, increased the ease with which workers could have a job in the city while commuting in from the suburbs. In the United Kingdom, railways stimulated the first mass exodus to the suburbs. The Metropolitan Railway, for example, was active in building and promoting its own housing estates in the north-west of London, consisting mostly of detached houses on large plots, which it then marketed as "Metro-land". As car ownership rose and wider roads were built, the commuting trend accelerated as in North America. This trend towards living away from towns and cities has been termed the urban exodus.
Zoning laws also contributed to the location of residential areas outside of the city centre by creating wide areas or "zones" where only residential buildings were permitted. These suburban residences are built on larger lots of land than in the urban city. For example, the lot size for a residence in Chicago is usually 125feet deep, while the width can vary from 14feet wide for a row house to 45feet wide for a large standalone house. In the suburbs, where standalone houses are the rule, lots may be 85feet wide by 115feet deep, as in the Chicago suburb of Naperville. Manufacturing and commercial buildings were segregated in other areas of the city.
Increasingly, more people moved out to the suburbs, known as suburbanization. Moving along with the population, many companies also located their offices and other facilities in the outer areas of the cities. This has resulted in increased density in older suburbs and, often, the growth of lower density suburbs even further from city centers. An alternative strategy is the deliberate design of "new towns" and the protection of green belts around cities. Some social reformers attempted to combine the best of both concepts in the garden city movement.
In the United States, since the 18th century urban areas have often grown faster than city boundaries. Until the 1900s, new neighborhoods usually sought or accepted annexation to the central city to obtain city services. In the 20th century, however, many suburban areas began to see independence from the central city as an asset. In some cases, White suburbanites saw self-government as a means to keep out people who could not afford the added suburban property maintenance costs not needed in city living. Federal subsidies for suburban development accelerated this process as did the practice of redlining by banks and other lending institutions. Cleveland, Ohio is typical of many American central cities; its municipal borders have changed little since 1922, even though the Cleveland urbanized area has grown many times over. Several layers of suburban municipalities now surround cities like Cleveland, Chicago, and Philadelphia.
While suburbs had originated far earlier; the suburban population in North America exploded after World War II. Returning veterans wishing to start a settled life moved en masse to the suburbs. Levittown developed as a major prototype of mass-produced housing. At the same time, African Americans were rapidly moving north for better jobs and educational opportunities than were available to them in the segregated South. Their arrival in Northern cities en masse - in addition to race riots in several large cities such as Detroit, Chicago, and Philadelphia - further stimulated white suburban migration.
In the U.S., 1950 was the first year that more people lived in suburbs than elsewhere. In the U.S, the development of the skyscraper and the sharp inflation of downtown real estate prices also led to downtowns being more fully dedicated to businesses, thus pushing residents outside the city center.
Urban development in Canada has largely paralleled development in the United States. After World War II, large bedroom communities of single-family homes and shopping centres sprouted on the outskirts of Canadian cities.
However, Canada has far fewer suburban municipalities than the U.S. does. Many large cities, such as Winnipeg, Calgary, Edmonton, and Ottawa, extend all the way to, and even include the countryside. However, the fact that literal boundaries of suburbs are not present in Canada does not in any way eliminate suburbs per se. The boundaries of Canadian cities are under the jurisdiction of the Provinces and the Provinces have imposed city-suburb mergers. Vancouver and Montreal regions still have suburban municipalities, although their suburban areas are generally grouped into fewer cities than is typical in the United States. British Columbia created a "metropolitan" government for the Vancouver area in 1954, but the urbanized area has since grown well beyond it.
Today, Toronto has some of the largest suburban municipalities in North America, and the two largest suburbs in Canada are in this metro area. Mississauga (668,549) and Brampton (433,806) together claim 1.1 million inhabitants, and would be the third largest city in Canada if merged. Many Toronto suburbs have significantly improved on the suburban philosophy, adding a downtown to many suburban centers, notably Mississauga, Brampton, Vaughan and Markham. In 1998 the governmental structure was reorganized to include many of these formerly independent suburbs into the Greater Toronto Area (see Greater Toronto Area).
Vancouver has several large suburbs, with more than three quarters of a million people living in Surrey (the third largest suburb in Canada), Richmond, and Burnaby. Montreal has its two largest suburbs, Laval and Longueuil, as well as a suburban group of smaller municipalities neighbouring Montreal known as the West Island.
Many post-World War II American suburbs are characterized by:
In many parts of the developed world, suburbs are different from the American suburb, both in terms of population and in terms of what they represent. In some cases suburbs of cities outside of North America are economically distressed areas, inhabited by higher proportions of recent immigrants, with higher delinquency rates and social problems. Sometimes the notion of suburb may even refer to people in real misery, who are kept at the limit of the city borders for economic, social and where applicable some argue ethnic reasons. An example in the developed world would be the banlieues of France, or the concrete suburbs of Sweden. In most ways, the suburbs of most of the developed world are comparable to several inner cities of the U.S. and Canada.
In the UK, the government is seeking to impose minimum densities on newly approved housing schemes in parts of southeast England. The new catch phrase is 'building sustainable communities' rather than housing estates. However, commercial concerns tend to retard the opening of services until a large number of residents have occupied the new neighbourhood.
In the illustrative case of Rome, Italy, in the 1920s and 1930s, suburbs were intentionally created ex novo in order to give lower classes a destination, in consideration of the actual and foreseen massive arrival of poor people from other areas of the country. Many critics have seen in this development pattern (that was circularly distributed in every direction) also a quick solution to a problem of public order (keeping the unwelcome poorest classes together with the criminals, in this way better controlled, comfortably remote from the elegant "official" town). On the other hand, the expected huge expansion of the town soon effectively covered the distance from the central town, and now those suburbs are completely engulfed by the main territory of the town. Other newer suburbs were created at a further distance from them.In China, the term suburb is new, although suburbs are already being constructed rapidly. Many new suburban homes are similar to their equivalents in the United States, primarily outside Beijing and Shanghai, which also mimic Spanish and Italian architecture.
In Malaysia, suburbs are common, especially outside the Klang Valley, which is the largest conurbation in the country. These suburbs also serve as major housing areas and commuter towns. Terraced houses, semi-detached houses and shophouses are common concepts in suburbs. In certain areas such as Klang, Subang Jaya and Petaling Jaya, suburbs form the core of these places. The latter one has been turned into a satellite city of Kuala Lumpur. Suburbs are also evident in other smaller conurbations including Ipoh, Johor Bahru, Kota Kinabalu, Kuching and Penang.
Suburbs typically have more traffic congestion and longer travel times than traditional neighborhoods. Only the traffic within the short streets themselves is less. This is due to three factors: almost-mandatory automobile ownership due to poor suburban bus systems, longer travel distances and the hierarchy system, which is less efficient at distributing traffic than the traditional grid of streets.
In the suburban system, most trips from one component to another component requires that cars enter a collector road, no matter how short or long the distance is. This is compounded by the hierarchy of streets, where entire neighborhoods and subdivisions are dependent on one or two collector roads. Because all traffic is forced onto these roads, they are often heavy with traffic all day. If a traffic accident occurs on a collector road, or if road construction inhibits the flow, then the entire road system may be rendered useless until the blockage is cleared. The traditional "grown" grid, in turn, allows for a larger number of choices and alternate routes.
Suburban systems of the sprawl type are also quite inefficient for cyclists or pedestrians, as the direct route is usually not available for them either. This encourages car trips even for distances as low as several hundreds of meters (which may have become up to several kilometres due to the road network). Improved sprawl systems, though retaining the car detours, possess cycle paths and footpath connecting across the arms of the sprawl system, allowing a more direct route while still keeping the cars out of the residential and side streets.