Social classes are the hierarchical arrangements of people in society as economic or cultural groups. Class is an essential object of analysis for sociologists, anthropologists, political economists and social historians. In the social sciences, social class is often discussed in terms of 'social stratification'.

In sociology and political philosophy, the most basic class distinction is between the powerful and the powerless. In Marxist theory and historical materialism, social class is caused by the fundamental economic structure of work and property. Various social and political theories propose that social classes with greater power attempt to cement their own ranking above the lower social classes in the social hierarchy to the detriment of the society overall. By contrast, conservatives and structural functionalists have presented class difference as intrinsic to the structure of any society and to that extent ineradicable. Social classes with a great deal of power are usually viewed as "the elites" within their own societies.