LEADERS of the 75 Communist parties meeting in Moscow—and those conspicuously absent—often argue bitterly about what their faith, Marxism, means. More interesting is the question of what Marxism does.

The word “Marxism” (and “Marxist”) is thrown around a lot these days. But much like “CRT,” few seem to understand it. Having read Marx and taught economics, here’s a rough, one-page summary.

Discover the story of Marxism in this simplified overview. Learn about its key concepts, the ideas of Karl Marx, and how Marxism has influenced political and social movements throughout history.