A film poster is a poster used to promote and advertise a film primarily to persuade paying customers into a theater to see it. Studios often print several posters that vary in size and content for various domestic and international markets. They normally contain an image with text. Today's posters often feature printed likenesses of the main actors. Prior to the 1980s, illustrations instead of photos were far more common. The text on film posters usually contains the film title in large lettering and often the names of the main actors. It may also include a tagline, the name of the director, names of characters, the release date, and other pertinent details to inform prospective viewers about the film.

A poster is a large sheet that is placed either on a public space to promote something or on a wall as decoration. Typically, posters include both textual and graphic elements, although a poster may be either wholly graphical or wholly text. Posters are designed to be both eye-catching and informative. Posters may be used for many purposes. They are a frequent tool of advertisers, propagandists, protestors, and other groups trying to communicate a message. Posters are also used for reproductions of artwork, particularly famous works, and are generally low-cost compared to the original artwork. The modern poster, as we know it, however, dates back to the 1840s and 1850s when the printing industry perfected colour lithography and made mass production possible.