Such connotations are less common in other countries, where deprived areas may be located in outlying parts of cities. For instance, in Paris, Vienna, Melbourne, Sydney or Amsterdam, the inner city is the most prosperous part of the metropolis, where housing is the most expensive, and where elites and high-income individuals dwell. Poverty and crime are more associated with the distant suburbs. The French word for "suburb" ("banlieue) often has a negative connotation, especially when used in the plural.
The peculiar American sociological usage is rooted in the middle 20th century. When automobiles became affordable in the United States, many middle and high-income residents, who were mostly white, moved to suburbs to have larger homes, less crime and less diversity. The loss of taxes caused many inner city communities to fall into urban decay. Late in the century, many such areas underwent gentrification, especially in the Northeast and West coast, depriving them of the "inner city" label despite their unchanged location.
Regardless of their wealth, inner city areas tend to have higher population densities then outer suburbs, with more of the population living inside multi floored townhouses and apartments.
The thriving of "old urbanism" in inner cities, in which prosperous individuals and families move into formerly poor neighborhoods, is known as gentrification.