Documentaries aim to document real events using actual footage or reconstruction. While footage may be authentic, directors still construct the presentation through camerawork, lighting, and editing. To make documentaries coherent and engaging, filmmakers borrow techniques from fiction like pacing and structure. John Grierson first defined documentaries in 1926 as the "creative treatment of actuality." John Corner later identified five central documentary elements: observation to place viewers as eyewitnesses, interviews, dramatization of events, carefully composed shots, and an expository argument or point of view. Documentaries can be fully narrated, follow a "fly on the wall" approach, use mixed techniques, or be self-reflexive acknowledging the camera.