Marxism is the system of political thinking named after Karl Marx, a German writer in the 1800s. The heart of it is this claim: the big changes in history happen because of a struggle between social classes — especially between people who own the factories, land, and money, and people who have to sell their work to live. Marx thought that struggle would, in the end, lead to a different kind of society in which that ownership was shared. That is the theory. In real talk, people use Marxism much more loosely. Some mean “anything left-wing.” Some mean the official line of a communist party. Some mean only what Marx himself wrote, and they argue that later leaders changed it. Scholars do not all agree on which reading is fair, so it is honest to say: Marxism is a family of ideas, not one frozen page. In a Taiwan classroom you will mostly meet it in history — next to the Soviet Union, China, and the Cold War — as a named school of thought, not as a word for “being unkind” or “being poor.” It is the thinking. Words like communism and socialism sit nearby, but they are not perfect copies of it.