There are several types of documentaries: 1) Fly on the wall documentaries observe subjects without commentary or narration, allowing viewers to form their own conclusions. 2) Fully narrated documentaries directly explain the visuals with a voiceover. 3) Self-reflective documentaries acknowledge the camera and allow subjects to speak directly to the filmmaker, drawing attention to the constructed nature of reality. 4) Mixed documentaries combine interviews, observation, and narration to link styles and tone.