Ephemeral film

Ephemeral film, as defined by film archivist Rick Prelinger[?], is film made for a specific purpose other than as a work of art: the films were designed to serve a specific pragmatic purpose. That is, the genre excludes most well-known film genres such as western film and comedies, and is composed of e.g. advertising films, industrial films, police training films, social guidance films, and home movies, among others. Prelinger estimates that the genre includes of hundreds of thousands films and, as such, is the largest genre of films, but that half or more of the films have been lost to neglect.

The films are often used as b roll[?] in documentary films, for instance the social guidance film The Terrible Truth[?] appears, desaturated in Ron Mann[?]'s film Grass[?] as an example of what he perceives as hysteria over drug abuse, as well as an example of the slippery slope fallacy.

Prelinger and other film archivists generally consider the films interesting for their sociological or anthropological value: for instance, a mental hygiene film instructing children to be careful of strangers may seem laughable by today's standards, but the film may show important aspects of society which were documented unintentionally: hairstyles, popular fashions, landscapes, technological advances, etc.