A movie trailer or movie preview is an assortment of film clips advertising a feature film. Using a combination of edits, title cards, music and voice-over, a trailer tries to convey the central premise, characters and circumstances of the film. Movie trailers received their name by originally playing after the main feature, thereby "trailing" the movie. Today trailers precede a feature film.
A teaser is a short movie trailer, often running only 30 seconds. A teaser presents only the bare minimum of ideas or concepts behind a film. Sometimes teasers do not include footage from the film at all, relying instead on voice-over and title captions. Teasers often appear long before a film is released.
A theatrical trailer is longer, providing a more fleshed-out version of the film. For some blockbuster movies, there may be more than one theatrical trailer released.
Like feature films, trailers have their own ratings system. Ratings for films and trailers are monitored and approved by the Motion Picture Association of America (MPAA). A green band trailer opens with a disclaimer on a green background, approving the trailer for "appropriate audiences." Green band trailers may play before any film, regardless of the rating. A red band trailer's disclaimer, on a red background, approves the trailer for "restricted audiences only." Red band trailers only play before films rated "R" or above. However, both trailer types are available online.
Historically, trailers have rarely been made by the studios financing the films or by the filmmakers. A small group of independent production companies specialize in creating movie trailers. Trailers, like films, have adapted their style toward modern tastes, and these companies play a big part in shaping our ever-changing tastes.
As of 2007, movie trailers are the third most watched videos online. The first recorded movie trailer appeared after the 1912 film, "The Adventures of Kathlyn." As public interest in movie trailers grew, an annual "Golden Trailer Awards" was established, where the best and worst trailers of the year are recognized.