A counterculture (also written counter-culture) is a subculture whose values and norms of behavior deviate from those of mainstream society, often in opposition to mainstream cultural mores.
A countercultural movement expresses the ethos, aspirations, and dreams of a specific population during a well-defined era. When oppositional forces reach critical mass, countercultures can trigger dramatic cultural changes.
Prominent examples of countercultures in Europe and North America include Romanticism (1790-1840), Bohemianism (1850-1910), the more fragmentary counterculture of the Beat Generation (1944-1964), the Hippie counterculture (1963-1974) and Hipsterism (2000's).
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