Documentaries aim to document and report factual information through footage, interviews, and observation. There are various types of documentaries including fully narrated, fly on the wall, verité, and cinema verité. Documentaries rely on human subjects and use exposition, which is the line of argument or narrative, to tell a story. Exposition can be plain, direct, indirect, or hidden. John Grierson coined the term "documentary" and defined it as the creative treatment of actuality for the purposes of education or persuasion.