trailer terminology

Trailer- a short piece of film (no longer than 2:30min) that is created to promote a film and deliver a plot summary. Trailers cannot show too much about a film (like spoilers), as it is designed to entice the audience and leave them wanting to see more of the film.

Teaser-an especially short type of trailer (usually 30sec) released long before the film or trailer that doesn't explain any of the premise or plot but is usually made just to generate hype for the film.

Plot Summary- a three act structure, similar to a film itself, only condensed into a trailer which basically establishes the premise, a climax and a montage of the best moments of the film (often accompanied by an orchestral piece that is signature to the film).

Voice-Over- a common convention of (though not exclusive to) action movies. Which is spoken in a deep voice and serves to explain the premise of the film.

Music-this is often used to set the overall tone of the film, though the music in the trailer is sometimes not from the film itself. The music found in the trailer may be the score of the film or another film, 'Library' music specifically composed for the trailer, or popular well known music from other artists.
Cast- the cast are the stars of the film, often times they warrant mention during a trailer, as do the director or producer if their previous works are well known or acclaimed

Billing block- a list of the cast and crew, often used at the end of trailers and on the movie poster

Sound Mix- Scenes of the trailer that use sound effects or enhance the stereophonic sound are achieved with a multichannel sound mix

Video resolution- the picture qualtity of the trailer. Trailers are distributed in HD with the highest possible quality, up to 1080p