Documentaries aim to report real events through actual footage or reconstruction. They can include narrators who were present or not. Common documentary types include fully narrated, "fly on the wall" with no crew acknowledgement, and those using interviews, observation, and narration. Documentaries construct reality through techniques like mise-en-scène, dramatization, and exposition, even when using actual footage. While they may simply describe events, documentaries can provide analysis and knowledge to viewers.