Trailers are designed to complement film posters and marketing campaigns by informing and exciting potential audiences about films. They help audiences understand the genre and plot of a film. Trailers are aimed at the same target audience as the film and highlight elements that will attract that audience, such as sparkly elements for children's films. Trailers are shown on TV, in cinemas, and online on various sites and film websites. Their goal is to grab audience attention through unique selling points like popular actors, genre mixes, or special effects. Timing of trailer releases is also important to build excitement but not be too early or late.