Well, as I grew up and navigated the 'isms' Communism seemed to me to be a perversion of Socialism with totalitarianism thrown in as a sort of bonus. I know there were variations, such as Stalanism and Trotskyism and I suppose Leninism, and we haven't even journeyed back to Marxism (I never heard of Engelism but by now I'm on a roll).
Communism also suffered from its adherents giving information to and taking direction from foreign governments, unless they happened to already be in Russia.
In short, Communism seemed to be whatever the boss and his henchmen said it was. As the bosses got older along with the workforce, it seemed to peter out until Gorby made his legendary visit to an American supermarket.
Communism also claimed to be proudly atheistic while yet suffering all the disadvantages of slavish beliefs without evidence. (And Communists didn't believe in Darwin).