Documentary films differ from the typical Hollywood movie because of one clear reason. While movies tend to be fictional stories acted out by known celebrities or striving stars, documentaries are non-fictional stories that are perhaps narrated by a single individual. The goal of a documentary is not to develop a fictional story, but essentially to tell a realistic and true story by presenting facts and interviews.
Documentary texts are supposedly those which aim to document reality, attempting veracity in their depiction of people, places and events. However, the process of mediation means that this is something of a oxymoron, it being impossible to re-present reality without constructing a narrative that may be fictional in places.Certainly, any images that are edited cannot claim to be wholly factual, they are the result of choices made by the photographer on the other end of the lens.