http://movies.nytimes.com/movie/238598/What-Happened-to-Mary/overview
Trailers, which date from 1912, when they were no more than the most basic of verbal communications informing audiences of what could be seen at a given venue a week hence, originally trailed the feature and were printed on the trailing portion of the feature’s print stock, which hitherto was used to protect the print.
When exhibited, the trailer indicated that the “program” of short films in a given theater had come to an end, and was expected to encourage the audience to leave and make way for the next group of paying customers.
Within a decade, however, the basic “text-only” trailer was combined with scenes, cast info, title cards and a marketing message, embraced by audiences, becoming ubiquitous in the film industry, and moving to the front of the program. The name, however, remains as a reminder of its humble origin.
I use the term “movie trailers” in the broadest sense to refer to what ought, more strictly, be called previews of coming attractions. By that I mean audio-visual entities used to market and advertise other audio-visual entities.
–A film used to promote a film;
–A video used to promote a video;
–A tv commercial used to promote a tv show;
–A film used to promote a video game;
–or a tv commercial used to promote a film.
Nota Bene: A trailer is always in a temporal relationship to the entertainment it markets. Typically, it comes before, although re-release trailers typically assume prior acquaintance with the film and its original release.
Here’s a comprehensive list of all the different kinds of av materials that fit the definition above, and deserve, at least to my mind, to be considered “trailers.”
Clips – footage from the feature distributed ahead of release as a literal “pre-view.” (See Entertainment Tonight, and increasingly, the feature’s website, for examples.)
Featurettes – Behind-the-scenes, “making-of” footage edited into a film about a film, or a TV show about a TV show. They used to be televised to fill out the time slot; now they are routinely included on the DVD and at the film or TV show’s website.
[youtube=http://www.youtube.com/watch?v=wUtr_iRgb4U ]
Teasers – Advance announcement of a coming attraction, typically 6 months to a year ahead of release, intended to promote awareness. Often, these short, conceptually ambitious “announcements” lack footage from the film itself, since the film itself hasn’t yet been shot or edited.
Standard Trailer (:90 – 2:30 in length) – a short film promoting a feature, combining story details, scenes from the feature, cast run, titles and release information. Typically exhibited theatrically 2-3 months before the film’s release.
TV Spot – Short trailer designed for TV exhibition immediately before and during the period of the film’s release. 10, 15, 30, & 60 seconds typically.
(Video) Game trailer – a trailer for a gaming entertainment and/or experience. (e.g. World of Warcraft; Sims; Farmville)
(Video) Game TV Spot – a TV spot for a gaming entertainment and/or experience.
Long Trailer – the Motion Picture Association of America allows each major studio to produce and exhibit one 4:00 minute trailer per year. The long trailer is usually produced for the distributor’s most high-profile (or “tentpole”) release.
Bloopers & Out-takes – materials from the production that will not be used in the feature, but which capture some entertaining or interesting aspect of the shoot itself.
EPK’s (Electronic Press Kits) — Interviews with production staff and cast, intended for the promotion of the film and distributed to journalists
Mashups – User Generated Trailer, combining the trailers for two very different movies into one, humorous “fake” movie preview.