perhaps a more complete discussion can be found on the wikipedia.
http://en.wikipedia.org/wiki/CommunismCommunism in its original meaning is a social theory and political movement for the direct and communal control of society towards the common benefits of all members, the society being the communist society, see below. See also Religious communism. The dominant tendency within the communist movement is inspired by Karl Marx's theory. Within Marxist communism the largest trends are inspired by the writings and actions of Vladimir Lenin.
During the 20th century, communism, or communism theory is often used to describe philosophies and practices of Marxism, Leninism, Stalinism, Trotskyism and Maoism. Whilst the common denominator is Marxism, some of them are nonetheless in conflict. The most influential branches of the communism tree are: the teachings of Marx/Engels/Lenin/Stalin, Marxism->Trotskyism and Marxism->Leninism->Maoism.
Some other, lesser known flavors are Council Communism, De Leonism and Left Communism.
Communism, or communist society is the name of the social formation, which, according to Marxism is a classless society in which all property is owned by the community as a whole and where all people enjoy equal social and economic status.
Marxists believe that just as society has transformed from feudalism to capitalism, it will transform into socialism and eventually communism. However the method by which this transformation occurs distinguishes communists from other socialists, in that communists believe that this will be accomplished by revolutionary means.
According to Lenin's approach the first step of the long term process of developing a communist society is a revolutionary seizure of political power; in Marxist terms, the domination of the bourgeoisie is to be replaced by the domination of the working class. In Marxist literature this political stage is called the dictatorship of the proletariat. Lenin argued that the revolution would occur first in less developed nations, such as Russia, and would require a vanguard of the proletariat composed of a relatively small tightly organized communist party.
Other communist movements, primarily Libertarian Socialism, differ with Leninism over the issue of the nature or importance of the party, and support for the idea of a government separate to working people's councils.
Communist parties are in power in People's Republic of China, Vietnam, Laos, North Korea, and Cuba. However, save Cuba, these nations are not truly communist and are in many ways authoritarian and capitalist.
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