Documentary films make up a broad category of nonfictional motion pictures intended to document some side of reality primarily for the purpose of instruction or maintaining a historical record this is because to make people remember the past history . A documentary film was originally shot on film stock the only medium available but now includes video and digital productions that can be either direct-to-video, made as a television program or released for screening in cinemas.
Things that documentaries use. A over talk of a person explaining what is happening. The over voice had to be clear and understandable when he or she explains something. If there is a wild life documentary there will be use a over talk. If it is a real life story then there will be lots of l-cuts. For example there is a interview there person that is getting interviewed will be speaking but the clip will be examples of what they are talking about.