Trailers are commercials for upcoming films shown before movies play. They aim to attract audiences through exciting or funny clips without spoiling the film. Teaser trailers are shorter (1.5 minutes) and shown early in production to create mystery, while theatrical trailers are longer (2.5 minutes) and shown closer to release when more footage is available to give audiences a better sense of the movie. The purpose of both is to entice viewers to watch the upcoming film.

1. Media
Teaser trailer vs. Theatrical
trailer

2. Trailers
A trailer is 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. Trailers are now shown before the film
(or the a movie in a double feature) begins.
Trailers consist of a series selected shots from the film being
advertised. Since the purpose of the trailer is to attract an
audience to the film, these usually contain parts of the film that are
the most exciting or funny parts of the film keeping in mind that it
does not spoil parts of the film.
A trailer has to achieve that in less than 2
minutes and 30 seconds, the maximum length
allowed by the MPAA. Each studio or distributor
is allowed to exceed this time limit once a
year, if they feel it is necessary for a particular
film.

3. Differences between teaser and
theatrical trailer
In a teaser trailer the producers are indeed trying to "tease" the
potential target audience about the film, leaving them wanting more.
Later on in the development stages of the film, a more in-depth trailer
will be released. This is referred to as the theatrical trailer. There are
various similarities in a teaser and theatrical trailer but also major
differences.

4. Teaser trailer
• The most evident difference between a teaser and theatrical trailer is
their duration. A teaser trailer usually lasts for a minute and a half
because the producers are in the early stages of production therefore
meaning they do not have enough footage so they’re working with
whatever they have.
• Also, if the audience are shown too much footage they might get an
idea of what the film is about and therefore not bother watching it.
• Creates mystery
• Big budget films with larger target audiences

5. Theatrical trailer
• In total contrast, a theatrical trailer is generally two and a half
minutes. This is mainly due to the fact that the film is in its final days of
editing, and thus the producers have a greater material to work with.
• Shown closer to the release date
• Contains more footage of the movie