By social stratification we generally mean a system which ranks society into the hierarchy of people. Not only in the US exist social groups which stand out of the general image due to the extremity of their wealth, status or power. Social stratification is a trait of the whole society. It comes in generations so that children of the higher social stratum tend to be rich not only due to their prominent achievements but mainly because of the belonging to the upper social class. Social stratification can be seen all over the world, but various areas show the different extent of the gradation. The causes of social stratification have been defined differently by a number of theorists. Proponents of the action theory supposed that stratification is inherent to developed societies as a dominance hierarchy is essential to preserve the social structure and order. Followers of the Marxist theory supposed that belonging to a certain stratum is defined by one’s relationship to the means of production. It worked almost as if the ruling class owned the working class due to their interrelations. K. Marx believed that the capitalist society is a favorable ground for the internal conflicts which will, after all, give a way to communist societies.
The theory of structural functionalism developed by Kingsley Davis and Wilbert Moore is a controversy to the previous theory of stratification. The founders argued that the stratification plays an important role in smooth functioning of a society. It works as a form of motivation for individuals to strive for a better education in order to achieve a high-income job a move to the upper social stratum.