From MarxWiki

As relevant to Marx, communism is a specific form of the broader political and economic ideology of socialism. Its ideology may be seen as espousing Marxism; in The Communist Manifesto Marx equated the Communist platform with his own ideas about class and the inevitability of the exploited workers' revolution. What distinguishes communism from socialism, aside from its more explicitly Marxist origins, is its insistence on the eventual dissolution of the governing class, so that communist society ultimately consists of rule by the proletariat.