Okay, the basis of Marxism is that our current system, capitalism, is based around two classes, the bourgeoisie and the proletariat. The bourgeoisie own the means of production, and the proletariat own nothing but their labor, and so must sell themselves for a wage to earn enough money to survive. Marx said that all of history is driven by class struggle. Not necessarily the modern class struggle of bourgeois vs. proletarian, but always, the events of history are caused by the tensions between social groups/classes who have irreconcilable differences (like slaves vs. slaveowners, or farmers vs. herders). The bourgeois are interested in generating as much profit as possible, while the proletariat are interested in having wages as high as possible. These two cannot co-exist easily, because the boss always wants to cut costs by lowering wages, and the workers always want to increase their wages by digging into the profits. Furthermore, the capitalist class is forced to follow this economic logic. Even if you're a generous boss who gives out a fair wage to his employees, that means you'll have less profit to re-invest back into your business, and will eventually be outcompeted by your more ruthless business rivals. This inevitably creates crises in capitalism, because at some point, the competition gets so tough that bosses can't even pay subsistence wages, and when the workers are paid so poorly they can't even afford to eat, they will revolt. This is the class struggle. It can be mitigated by government reforms (minimum wage, social welfare) and by unions that force the capitalists to pay better, but these will always be temporary measures that can't fix the inherent contradiction in capitalism. Marx believes that this contradiction will inevitably lead to a total social revolution where the workers rise up, seize the means of production for themselves, and institute socialism, and then when socialism has worked properly for a while, the state will wither away and we can have stateless communism where everyone lives in freedom and abundance.