Documentary film, according to the Encyclopaedia of Brittanica, is a motion picture that shapes and interprets factual material for purposes of education or entertainment.
A documentary theorist named Bill Nichols, claimed that all films can be called documentaries based on the principle that all films provide information about the culture that produces them.
Nichols divided documentaries into 2 sub-categories: Wish fulfilment, which references all fictional films, and Social Representation referencing what we denote documentaries as. However, distinguishing between these 2 categories is made difficult by the fact that they feature similar conventions. For example mise-en-scene is used in both categories but in fiction films it is fabricated whereas in documentary films it is found in reality, filmmakers and filmmaking equipment are used to produce both but regularly appear on-screen in documentaries whilst staying passive in fiction films.
The main idea behind Bill Nichols theory is that the distinction between fiction films and documentaries is a sliding scale and whilst he separated them into the categories of wish fulfilment and social representation, in between these opposing sides is a large grey area that many films cross into resulting in difficulty to define and categories films as a whole.
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