Problems of big cities.
A city is a large and stable human settlements, urban area that differs from one country or a village in size, population density, importance, or legal status. The term derives from the analogous Latin civitas Italian cities, and derives from the etymology of civilization. A concise definition of city could be: the concentration of population and functions, with stable structures and one territory. This definition has the advantage of greater flexibility. Is the administrative town of the title belongs to the municipalities who have been formally granted by virtue of its importance and varies according to the legal systems of states.
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Typically, a city consists of residential areas, industrial areas and commercial and administrative sectors, which may also affect a wider geographic area. Most of the area of a city is occupied by the urban fabric (houses, streets, roads), lakes, rivers and parks are often a minority. The word town can be used for a resort town whose population exceeds a given limit or for a location other in the same economic, political or cultural. Although the city is suitable for a reality which includes suburban areas and satellite, the term is not intended to indicate an agglomeration of separate entities or to indicate a larger “metropolitan area” consists of several cities, in which each act as a center for their part.
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There is no general definition of a city in the world, for example in Italy city status is conferred by the head of the state by decree, and when America was colonized, the new inhabitants enthusiastically gave the name “city” to their new settlements, arguing that they would one day become very large. For example, Salt Lake City was a village of 148 souls, who immediately planned a road system and founded Great Salt Lake City. A century and a half later, the village has in fact reached the size of a city.