Making a film is expensive, so films must earn a significant amount at the box office to recoup costs. Marketing budgets typically equal half to three times production budgets to promote films through trailers, interviews, posters and more. Trailers shown in theaters, online and on TV are especially important for generating buzz and enticing audiences to watch a film. Effective trailers use techniques like cliffhangers, comedy, action and music to create an exciting atmosphere and hint at the genre.