The term "social mobility" describes the nature and amount of change in social position over time. In principle, this change can be defined for any social entity. Thus, one can study the "collective mobility" of classes, ethnic groups, or entire nations in terms of, for example, average health status, literacy, education, or gross domestic product per capita. More commonly, the term is used in connection with the movement of individuals or families. However, even though social mobility typically is defined with respect to micro units of society, the pattern of mobility across those units generally is considered a core characteristic of a society's social structure, and the study of this mobility generally is recognized as a fundamental area of macro-level sociology.

Social mobility typically is conceptualized in terms of the quantity of movement and the distribution of its direction and distance. The different rates that together...