Documentaries document real events using footage of what actually occurred as well as reconstructions to show viewers what happened. They typically use either a narrator's voiceover or interviews with participants to provide context and meaning. There are several types of documentaries including fully narrated documentaries that use an off-screen narrator to explain visuals, fly-on-the-wall documentaries that observe actions without acknowledging the camera, and mixed documentaries that combine interviews, observations, and narration to advance an argument. Documentaries also include docudramas that reenact events and docusoaps that follow individuals' lives in a serialized format.