Trailer (computing)

In information technology, trailer refers to supplemental data placed at the end of a block of data being stored or transmitted, which may contain information for the handling of the data block, or just mark its end.

In data transmission, the data following the end of the header and preceding the start of the trailer is called the payload or body.

It is vital that trailer composition follow a clear and unambiguous specification or format, to allow for parsing. If a trailer is not removed properly, or part of the payload is removed thinking it is a trailer, it can cause confusion.

Examples

Trailer

Trailer may refer to:

Transportation

Shelter

Computing

Trailer (promotion)

A trailer (also known as a preview or coming attraction) is an advertisement or a commercial for a feature film that will be exhibited in the future at a cinema. The term "trailer" comes from their having originally been shown at the end of a feature film screening. That practice did not last long, because patrons tended to leave the theater after the films ended, but the name has stuck. Trailers are now shown before the film (or the A-movie in a double feature) begins.

Movie trailers have now become popular on DVDs and Blu-rays, as well as on the Internet and mobile devices. Of some 10 billion videos watched online annually, film trailers rank third, after news and user-created video. The trailer format has also been adopted as a promotional tool for television shows, video games, books, and theatrical events/concerts.

History

The first trailer shown in a U.S. film theater was in November 1913, when Nils Granlund, the advertising manager for the Marcus Loew theater chain, produced a short promotional film for the musical The Pleasure Seekers, opening at the Winter Garden Theatre on Broadway. Loew adopted the practice, which was reported in a wire service story carried by the Lincoln, Nebraska Daily Star, describing it as "an entirely new and unique stunt", and that "moving pictures of the rehearsals and other incidents connected with the production will be sent out in advance of the show, to be presented to the Loew’s picture houses and will take the place of much of the bill board advertising". Granlund was also first to introduce trailer material for an upcoming motion picture, using a slide technique to promote an upcoming film featuring Charlie Chaplin at Loew's Seventh Avenue Theatre in Harlem in 1914.

Trailer music

Trailer music (a subset of production music) is the background music used for film previews, which is not always from the film's soundtrack. The purpose of this music is to complement, support and integrate the sales messaging of the mini-movie that is a film trailer. Because the score for a movie is usually composed after the film is finished (which is much after trailers are released), a trailer will incorporate music from other sources. Sometimes music from other successful films or hit songs is used as a subconscious tie-in method.

The music used in the trailer may be (or may have suggestive derivatives from):