The genre is composed of advertising films, educational films, industrial films, police training films, social guidance films, and government-produced films. While some may borrow themes from well-known film genres such as western film and comedies, what defines them is a sponsored rhetoric to achieve the sponsor's goals, rather than those of the creative artist.
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, ethnographic or evidentiary 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, technological advances, landscapes, etc.
Prelinger estimates that the genre includes perhaps 400,000 films and, as such, is the largest genre of films, but that one-third to one-half of the films have been lost to neglect. In recent years the archival moving image community has taken greater notice of sponsored film, and key ephemeral films are now being preserved by specialized, regional and national archives.