Marxism is a conflict theory with argues that there is conflict between different groups within society. The way society produces the things we need (mode of production) exploits the proletariat because the bourgeoisie (ruling class) benefit from the working class labour.
Capitalism is unfair as it allows the rich to get rich and poor to get poorer. The ruling class live in lavish conditions whilst their workers are in relative poverty. Social relation of production is the conflict between workers and owners. Infrastructure is also unfair. The system is called a superstructure, which includes media, education, law etc. They are designed to keep the divide between the poor and the rich. All types of ideology trick us into thinking that capitalism is fair – the ruling class make us believe that it is and we fall into a state of false-class consciousness, where we believe that our lives are good.
Ideological State Apparatus is using a superstructure to distract us from the fact that the working class are exploited. Repressive state apparatus is using force to control the masses.
Because the capitalist infrastructure is so unfair, we need something to convince us otherwise. This is known as a superstructure.
We accept exploitation is two ways: ideological state apparatus, which makes us unaware of our exploitation through false class consciousness, and repressive state apparatus.