Film theory is a set of scholarly approaches  within the academic discipline of cinema studies that questions the essentialism of cinema and 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.
French philosopher Henri Bergson's Matter and Memory (1896) has been cited as anticipating the development of film theory during the birth of cinema. Bergson commented on the need for new ways of thinking about movement, and coined the terms "the movement-image" and "the time-image". However, in his 1906 essay L'illusion cinématographique (in L'évolution créatrice; English: The cinematic illusion in Creative Evolution), he rejects film as an exemplification of what he had in mind. Nonetheless, decades later, in Cinéma I and Cinema II (1983-1985), the philosopher Gilles Deleuze took Matter and Memory as the basis of his philosophy of film and revisited Bergson's concepts, combining them with the semiotics of Charles Sanders Peirce.
Early film theory arose in the silent era and was mostly concerned with defining the crucial elements of the medium. It largely evolved from the works of directors like Germaine Dulac, Louis Delluc, Jean Epstein, Sergei Eisenstein, Lev Kuleshov, and Dziga Vertov and film theorists like Rudolf Arnheim, Béla Balázs and Siegfried Kracauer. These individuals emphasized how film differed from reality and how it might be considered a valid art form. In the years after World War II, the French film critic and theorist André Bazin reacted against this approach to the cinema, arguing that film's essence lay in its ability to mechanically reproduce reality, not in its difference from reality.
In the 1960s and 1970s, film theory took up residence in academia importing concepts from established disciplines like psychoanalysis, gender studies, anthropology, literary theory, semiotics and linguistics. However, not until the late 1980s or early 1990s did film theory per se achieve much prominence in American universities by displacing the prevailing humanistic, auteur theory that had dominated cinema studies and which had been focused on the practical elements of film writing, production, editing and criticism. American scholar David Bordwell has spoken against many prominent developments in film theory since the 1970s, i.e., he uses the derogatory term "SLAB theory" to refer to film studies based on the ideas of Saussure, Lacan, Althusser, and Barthes. Instead, Bordwell promotes what he describes as "neoformalism."
During the 1990s the digital revolution in image technologies has influenced film theory in various ways. There has been a refocus onto celluloid film's ability to capture an "indexical" image of a moment in time by theorists like Mary Ann Doane, Philip Rosen and Laura Mulvey who was informed by psychoanalysis. From a psychoanalytical perspective, after the Lacanian notion of "the Real", Slavoj ?i?ek offered new aspects of "the gaze" extensively used in contemporary film analysis. There has also been a historical revisiting of early cinema screenings, practices and spectatorship modes by writers Tom Gunning, Miriam Hansen and Yuri Tsivian.
In Critical Cinema: Beyond the Theory of Practice (2011), Clive Meyer suggests that 'cinema is a different experience to watching a film at home or in an art gallery', and argues for film theorists to re-engage the specificity of philosophical concepts for cinema as a medium distinct from others.