A counterculture is a culture whose values and norms of behavior differ substantially from those of mainstream society, sometimes diametrically opposed to mainstream cultural mores. A countercultural movement expresses the ethos and aspirations 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 the Western world include the Levellers (1645–1650), Bohemianism (1850–1910), the more fragmentary counterculture of the Beat Generation (1944–1964), and the globalized counterculture of the 1960s (1965–1973). Countercultures differ from subcultures.

Culture is a concept that encompasses the social behavior, institutions, and norms found in human societies, as well as the knowledge, beliefs, arts, laws, customs, capabilities, and habits of the individuals in these groups. Culture is often originated from or attributed to a specific region or location.