<Table> <Tr> <Td> </Td> <Td> The examples and perspective in this article deal primarily with the United States and do not represent a worldwide view of the subject . You may improve this article, discuss the issue on the talk page, or create a new article, as appropriate . (June 2012) (Learn how and when to remove this template message) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> The examples and perspective in this article deal primarily with the United States and do not represent a worldwide view of the subject . You may improve this article, discuss the issue on the talk page, or create a new article, as appropriate . (June 2012) (Learn how and when to remove this template message) </Td> </Tr> <P> A trailer (also known as a preview or coming attraction) is a commercial advertisement for a feature film that will be exhibited in the future at a cinema, the result of creative and technical work . 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 begins . </P> <P> Movie trailers have now become popular on DVDs and Blu - ray discs, 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 . </P>

Why is a movie trailer called a trailer