A trailer is a short film used to promote a movie. It is often a clip of an action scene or a few moments from the film and a voice over that explains what the film is about. It also usually has the title of the film and any on-screen text, such as the studio production logo or the release date. Trailers are also used to advertise television shows, video games, books and theatrical events.

Originally, movie trailers were used to advertise the film in theaters and cinemas. They were a form of cinematic advertising that was developed in 1913 by Nils Granlund, who edited rehearsal footage from the play The Pleasure Seekers into a trailer that would play before films at the Marcus Loew theater chain.

The movie industry quickly began using trailers to market films and promote the opening of new movies. In the decades since, film marketing has become a massive industry that produces highly polished and effective trailers able to sell even bad movies to audiences.

Great trailers tell a riveting story that gets the audience emotionally invested in the film. This is a key element that helps them go viral. One of the most important things to keep in mind when making a trailer is the use of three act structure. This includes a cold open that introduces the main characters, setting and film’s premise; a middle that heightens conflict; and an end with a climax.

Another important aspect to consider when making a trailer is the use of dialogue. This is not something that should be overdone, but it can be a powerful tool when done right. Adding just a few lines of dialogue can add depth to a clip and make it feel more complete. It can also help create tension between the characters and increase the audience’s desire to see what will happen next.

In addition to dialogue, it is also important to consider the music that is being used in a trailer. Music can create a mood that will help the audience connect with the story and atmosphere of the movie. It can also be used to accentuate specific emotions or scenes in the trailer.

A trailer can include a lot of different clips from the film it is promoting. However, it is important to only include high-quality footage. Poor quality footage can ruin a trailer and detract from the overall message.

Also, a trailer should not include too many details about the film. It is important to leave enough mystery so that the audience will be intrigued and excited to see the full movie. This can be accomplished by only revealing a few major plot points and leaving the rest to the audience’s imagination.

It is also a good idea to include a cast run in a trailer, which is a list of the main actors and actresses that appear in the movie. This is often accompanied by the director’s name and the film’s production company. The cast run is typically featured near the beginning of a trailer, but it can also be included in the middle or at the end of the trailer.