Sociology explores the intersection of biography and history by relating the life of the individual to the operation of social institutions. From the analysis of passing encounters between individuals in the street to the investigation of broad-based international social movements, the student of sociology studies the subtle, yet complex ways in which her life interacts with the collective experience of others.
Sociology represents one of three distinct approaches to the study of human behavior.
Biology examines and explains behavior in terms of physiological processes, the activities of chemicals and organs in living things. Psychology looks at human behavior in terms of the development of a single ego from birth through adulthood and the role of that personality in human affairs. Sociology is interested in the situations and institutions that are produced by the interaction of two or more persons. Thus, 'social' action is always interaction. Social interactions are the basic data from which sociologists build analyses, that is, descriptions and explanations of human action.