A tankie with a Stalin avatar asks “what’s communism?” You can’t even make this up.
I’ll let Marx tell you:
“In this sense, the theory of the Communists may be summed up in the single sentence: Abolition of private property.”
-Manifesto of the Communist Party
Within the co-operative society based on common ownership of the means of production, the producers do not exchange their products; just as little does the labor employed on the products appear here as the value of these products, as a material quality possessed by them, since now, in contrast to capitalist society, individual labor no longer exists in an indirect fashion but directly as a component part of total labor.