A documentary is a film that attempts to "document" some aspect of real life. They're often wrongly assumed to be unbiased; in fact, the opposite is true: documentaries are the most biased form of film, because they incorporate not just the subject matter, but intrinsically the director's attitude towards the subject matter as well. My first film professor, who was a documentarian, said there are two main points to a documentary:
  • Elevation of the ordinary.
    Whereas feature films tend to showcase outlandish or fantastic stories and characters, documentaries find the exceptional in everyday life.
  • Giving a voice to those who have not had one.
    Everyone in Hollywood is good-looking, rich, talented, nauseating, etc. Documentaries seek out those who are not, or who at least may appear ordinary, but are just as real and distinguished as any actors.
Documentary as a film genre tends to get a bad rap as being too "intellectual" or just flat-out boring. Yes, there are a lot of bad documentaries, but there is also a plethora of utterly crappy Hollywood feature films as well. For a sampler of good feature-film documentaries, check out Four Little Girls, When We Were Kings, Thirty-Two Short Films About Glenn Gould, Gettysburg, Better Living Through Circuitry, and for a prime example of heavily-biased-documentary-with-attitude, anything by Michael Moore.