Social act refers to a basic unit of social behavior. According to Max Weber, "“Action is social in so far as, by virtue of the subjective meaning attached to it by the acting individual (or individuals), it takes account of the behavior of others and is thereby oriented in its course.” 
Alfred Schutz amplified this with the suggestion that such acts represented substantively meaningful experience emanating from our spontaneous life and based upon a preconceived project. 
The concept is particularly significant in the work of symbolic interactionists, social action theorists, existentialist and humanist sociologists and social psychologists.
- Weber, Max. Economy and Society: An Outline of Interpretive Sociology. Translated by G. Roth and C. Wittich. New York: Bedminster Press, 1968.
- Schutz, Alfred. On Phenomenology and Social Relations: Selected Writings. Chicago: University of Chicago Press, 1970, p. 125