社会階層
Social stratification is a term used in the social sciences to describe the relative social position of persons in a given social group, category, geographical region or other social unit. It derives from the Latin "strātum" (plural '; parallel, horizontal layers) referring to a given society's categorization of its people into rankings of socioeconomic tiers based on factors like wealth, income, social status, occupation and power. In modern Western societies, stratification is often broadly classified into three major divisions of social class: upper class, middle class, and lower class. Each of these classes can be further subdivided into smaller classes (e.g. "upper middle"). Social may also be delineated on the basis of kinship ties or caste relations.