There are two main social classes in all stratified societies, these are a ruling class and a subject class.

The ruling class owns and controls the means of production such as land, capital, labor, buildings and machinery.

There is not a fundamental contradiction or a conflict of interest between the two classes.

The ruling class exploits and oppresses the subject class in order to maintain and reinforce its advantages.

The institutions of superstructure (social institutions such as religion, law, political system etc.) serve to the ruling class and function as tools for the ruling class domination.