Looks like you don't have a firm understanding of what communism or Marxism is, so you attack it on the grounds that it allegedly caused a world war and killed hundreds of millions of people.

But communism never started a world war. And while many people have been killed in the name of communism, many people have also been killed in the name of capitalism, Christianity, you name it. It isn't clear why you think there is an inherent connection between "worker ownership of the means of production" and millions of deaths.

This isn't an opinion based on the merits of the ideas of communism or Marxism. Ignorance, it sems, is much easier to spread on the internet than logic and reason.