A trailer is a container that attaches to a vehicle and is used to carry goods. It can be pulled by a tractor or driven manually. Trailers can be found on commercial trucks, automobiles, and trains.

Trailers can be masterpieces of production (Venom, anyone?) or bite-sized entertainment that gets butts in seats (Aquaman). But they are, at the end of the day, a tool to sell tickets.

Traditionally, movie trailers ran before feature films at theaters. But with the advent of multi-screen cinemas and digital distribution, they have become an increasingly important standalone part of a film’s marketing campaign. Today, many studios release “red-band” trailers that are not shown on television, and develop extended campaigns with teasers, countdowns and even footage-less promotions announcing a trailer’s release. YouTube has also become a new sandbox for editors, who can create fascinating recuts of popular trailers such as Mary Poppins and The Shining.

The best movie trailers use short clips of the movie to build up a sense of anticipation and awe. They are visual tone poems, often synchronized to music and minimal patches of dialogue. They are also, in the words of one critic, “visual anaphoras that are anchored by the kinetic energy of editing.”

Many modern trailers use music and sound effects to convey the genre of the film they’re advertising. The distant sounds of battle in a war movie can tell the audience what they’re in for, while ambient futuristic noises can subtly hint at a science fiction film.

It’s also important to have a clear and concise tagline that describes the film. This can be a simple line such as “The world is not what it seems,” or a more complex tagline like, “Everything you see is not what it appears.”

Finally, the trailer needs to include a cast run, which is a list of the main actors and actresses in the film. It’s usually located at the top of the screen along with the title and production logos of the studio.

It’s also helpful to study the trailers of movies that are similar to your own. This will give you an idea of the shots and sound effects that will work well in your trailer, as well as the pace and narrative structure. It’s also important to decide whether or not to include a voiceover, which can be incredibly effective in setting the tone of the trailer. If you do include a voiceover, be sure that it is tone appropriate and clearly conveys the message of your trailer.