teaser

A teaser trailer (or simply a teaser) is a short trailer and a form of teaser campaign advertising that focuses on film and television programming. It is a videography pre-release film or television show advertisement. Short in length, teaser trailers contain little material from the advertised content to be released.
Frequently, they contain hinted, cryptic, curiosity-inducing messages. Methods of this nature are designed to pique audience interest and anticipation, as well as increase the hype of the advertised content before release of its trailer. The length of a teaser trailer is usually only around 20–30 seconds, noticeably shorter than the 2014 National Association of Theatre Owners guideline of two minutes for standard trailers. It is generally created during the shooting of the film or program and released before the completion of shooting.

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