Any ideology based on the communal ownership of all property and a classless social structure, with economic production and distribution to be directed and regulated by means of an authoritative economic plan that supposedly embodies the interests of the community as a whole. Karl Marx is today the most famous early theoretician of communism, but he did not invent the term or the basic social ideals, which he mostly borrowed and adapted from the less systematic theories of earlier French utopian socialists -- grafting these onto a philosophical framework Marx derived from the German philosophers Hegel and Feuerbach, while adding in a number of economic theories derived from his reinterpretation of the writings of such early political economists such as Adam Smith, Thomas Malthus, and David Ricardo. In most versions of the communist utopia, everyone would be expected to co-operate enthusiastically in the process of production, but the individual citizen's equal rights of access to consumer goods would be completely unaffected by his/her own individual contribution to production -- hence Karl Marx's famous slogan "From each according to his ability; to each according to his need." The Marxian and other 19th century communist utopias also were expected to dispense with such "relics of the past" as trading, money, prices, wages, profits, interest, land-rent, calculations of profit and loss, contracts, banking, insurance, lawsuits, etc. It was expected that such a radical reordering of the economic sphere of life would also more or less rapidly lead to the elimination of all other major social problems such as class conflict, political oppression, racial discrimination, the inequality of the sexes, religious bigotry, and cultural backwardness -- as well as put an end to such more "psychological" forms of suffering as alienation, anomie, and feelings of powerlessness.
The specifically Marxist-Leninist variant of socialism which emphasizes that a truly communist society can be achieved only through the violent overthrow of capitalism and the establishment of a "dictatorship of the proletariat" that is to prepare the way for the future idealized society of communism under the authoritarian guidance of a hierarchical and disciplined Communist Party.
A world-wide revolutionary political movement inspired by the October Revolution (Red Oktober) in Russia in 1917 and advocating the establishment everywhere of political, economic, and social institutions and policies modeled on those of the Soviet Union (or, in some later versions, China or Albania) as a means for eventually attaining a communist society.