Bill Nichols is a Swedish film critic and theorist known for founding the contemporary study of documentary film. He identified six modes of documentary: poetic, expository, observational, participatory, reflexive, and performative. The poetic mode uses cinematography and music to convey mood without direct commentary. The expository mode relies on voiceovers or subtitles to communicate an argument. The observational mode emphasizes unbiased observation of subjects' daily lives. The participatory mode involves greater filmmaker interaction and bias. The reflexive mode promotes truth by allowing viewers to draw their own conclusions from footage. The performative mode engages viewers with a story while also presenting factual information.