The document discusses social stratification, which refers to the division of society into hierarchical social classes. It defines social stratification as the unequal distribution of resources and power among social groups. Some key aspects covered include social classes, status, and roles. Social classes refer to large socioeconomic groupings, while status is one's standing and prestige. Roles refer to the expected behaviors associated with one's status. Theories on stratification like conflict theory and functional theory are also mentioned. Different types of stratification systems such as open and closed class systems are described.