If the means of production goods belong to the working class, this is a socialism. These element exist inside a capitalist society - employees owned enterprises.
The next step on the way to communism is destroying classes which on the Communist leaders opinion, are hostile to the Communist ideals: Cleric, intellectuals, Government structures, high-ranking managers etc. In the other word, according to the Marx' and Lenin' theory, Communism should destroy whole economical and political establishment.
Lenin first tried to implement these ideas into reality: in 1918 he declared "The red terror" and ordered to create giant concentration camp on the Russian North, where whole classes of Russian society were sent and tortured to death - many millions of people. They have been declared as "enemy of revolutionary people". The whole economy and infrastructure were destroyed. On the ruins of Old Russia the Communist created new society. The main goal of this society was to destroy the capitalist societies in the whole World. For this purpose they create a gigantic military economy, hostile to people. To create this military production the Communist leaders used slavery, violence, forced labor, mass killing those who was "not enough happy" by such Communism.
The same way the Communist leaders acted in other countries - North Korea, Cuba, Cambodia, China.
Related to a ideas of the French revolution - Liberté, égalité, fraternité which became a slogan of Communism: I saw by my own eyes, what they mean in the real life. May be I will tell you later.