A documentary film or documentary videography  is a non-fictional motion picture intended to document reality, primarily for instruction, education or maintaining a historical record.  Bill Nichols has characterized the documentary in terms of “a filmmaking practice, a cinematic tradition, and mode of audience reception [that remains] a practice without clear boundaries

The word “documentary” was coined by Scottish documentary filmmaker John Grierson in his review of Robert Flaherty’s film Moana (1926), published in the New York Sun on 8 February 1926, written by “The Moviegoer

Types of documentary films 

Participatory documentaries believe that it is impossible for the act of filmmaking to not influence or alter the events being filmed. What these films do is emulate the approach of the anthropologist: participant-observation. Not only is the filmmaker part of the film, we also get a sense of how situations in the film are affected or altered by their presence.

Reflexive documentaries do not see themselves as a transparent window on the world; instead, they draw attention to their own constructedness, and the fact that they are representations.

Performative documentaries stress subjective experience and emotional response to the world. They are strongly personal, unconventional, perhaps poetic and/or experimental, and might include hypothetical enactments of events designed to make us experience what it might be like for us to possess a certain specific perspective on the world that is not our own, e.g. that of black, gay men in Marlon Riggs’s Tongues Untied (1989) or Jenny Livingston’s Paris Is Burning (1991)