A metropolitan area or metro is a region consisting of a densely populated urban agglomeration and its surrounding territories which are sharing industries, commercial areas, transport network, infrastructures and housing. A metropolitan area usually comprises multiple principal cities, jurisdictions and municipalities: neighborhoods, townships, boroughs, cities, towns, exurbs, suburbs, counties, districts and even states and nations in areas like the eurodistricts. As social, economic and political institutions have changed, metropolitan areas have become key economic and political regions.
In the United States, a metropolitan statistical area (MSA) is a geographical region with a relatively high population density at its core and close economic ties throughout the region. Such regions are not legally incorporated as a city or town would be and are not legal administrative divisions like counties or separate entities such as states. As a result, sometimes the precise definition of a given metropolitan area will vary between sources. The statistical criteria for a standard metropolitan area were defined in 1949 and redefined as a metropolitan statistical area in 1983.
A census-designated place (CDP) is a concentration of population defined by the United States Census Bureau for statistical purposes only.
A core-based statistical area (CBSA) is a U.S. geographic area defined by the Office of Management and Budget (OMB). It contains a large population nucleus, or urban area, and adjacent communities that have a high degree of integration with that nucleus.
In 45 of the 50 states of the United States, the county is used for the level of local government immediately below the state itself. Louisiana uses parishes, and Alaska uses boroughs. In Connecticut, Massachusetts, and Rhode Island, some or all counties within states have no governments of their own; the counties continue to exist as legal entities, however, and are used by states for some administrative functions and by the United States Census bureau for statistical analysis. There are 3,242 counties and county equivalent administrative units in total, including the District of Columbia and 100 county-equivalents in the U.S. territories.
The census geographic units of Canada are the census subdivisions defined and used by Canada's federal government statistics bureau Statistics Canada to conduct the country's quinquennial census. These areas exist solely for the purposes of statistical analysis and presentation; they have no government of their own. They exist on four levels: the top-level (first-level) divisions are Canada's provinces and territories; these are divided into second-level census divisions, which in turn are divided into third-level census subdivisions and fourth-level dissemination areas.
An urban area is a human settlement with a high population density and an infrastructure of built environment. This is the core of a metropolitan statistical area in the United States, if it contains a population of more than 50,000.
In geography, statistics and archaeology, a settlement, locality or populated place is a community of people living in a particular place. The complexity of a settlement can range from a minuscule number of dwellings grouped together to the largest of cities with surrounding urbanized areas. Settlements include hamlets, villages, towns and cities. A settlement may have known historical properties such as the date or era in which it was first settled, or first settled by particular people. The process of settlement involves human migration.
Metropolitan areas of Mexico have been traditionally defined as the group of municipalities that heavily interact with each other, usually around a core city, in Mexico. The phenomenon of metropolization in Mexico is relatively recent, starting in the 1940s. Because of an accelerated level of urbanization in the country, the definition of a metropolitan area is reviewed periodically by the Mexican population and census authorities.
The U.S. State of New Jersey currently has nine statistical areas that have been delineated by the Office of Management and Budget (OMB). On July 21, 2023, the OMB delineated three combined statistical areas and six metropolitan statistical areas in New Jersey. As of 2023, the largest of these is the New York-Newark, NY-NJ-CT-PA CSA, which includes New Jersey's largest city, Newark, and capital, Trenton.
The U.S. State of California currently has 42 statistical areas that have been delineated by the federal Office of Management and Budget (OMB).
The United States Census Bureau defines a place as a concentration of population which has a name, is locally recognized, and is not part of any other place. A place typically has a residential nucleus and a closely spaced street pattern, and it frequently includes commercial property and other urban land uses. A place may be an incorporated place or it may be a census-designated place (CDP). Incorporated places are defined by the laws of the states in which they are contained. The Census Bureau delineates CDPs. A small settlement in the open countryside or the densely settled fringe of a large city may not be a place as defined by the Census Bureau. As of the 1990 census, 26% of the people in the United States lived outside of places.
The urbanization of the United States has progressed throughout its entire history. Over the last two centuries, the United States of America has been transformed from a predominantly rural, agricultural nation into an urbanized, industrial one. This was largely due to the Industrial Revolution in the United States in the late 18th and early 19th centuries and the rapid industrialization which the United States experienced as a result. In 1790, only about one out of every twenty Americans lived in urban areas (cities), but this ratio had dramatically changed to one out of four by 1870, one out of two by 1920, two out of three in the 1960s, and four out of five in the 2000s.
