What is a Documentary Film?

Rightly said by Alfred Hitchcock, Documentaries are non-fiction films that depicts reality for many purposes which can be educational, for giving Instructions or even to maintain a historical record. Documentaries come in handy for many work institutions to teach reality-based principles as they are much informative. Earlier documentaries were called as Actuality Films, which uses footages of real-life events, objects and places. Documentaries have evolved through years and has been loved by many viewers other than educators and scholars.