academic discipline studying film's relationship to reality, the arts, viewers & society
Film theory is a set of scholarly approaches within the academic discipline of film or cinema studies that began in the 1920s by questioning the formal essential attributes of motion pictures; and that now provides conceptual frameworks for understanding film's relationship to reality, the other arts, individual viewers, and society at large. Film theory is not to be confused with general film criticism, or film history, though these three disciplines interrelate.
Although some branches of film theory are derived from linguistics and literary theory, it also originated and overlaps with the philosophy of film.
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