Audio description, (AD) also referred to as a video description, described video, or more precisely visual description, is a form of narration used to provide information surrounding key visual elements in a media work (such as a film or television program, or theatrical performance) for the benefit of blind and visually impaired consumers. These narrations are typically placed during natural pauses in the audio, and sometimes overlap dialogue if deemed necessary. Occasionally when a film briefly has subtitled dialogue in a different language, such as Greedo's confrontation with Han Solo in the 1977 film Star Wars: A New Hope, the narrator will read out the dialogue in character. In museums or visual art exhibitions, audio described tours (or universally designed tours that include description or the augmentation of existing recorded programs on audio- or videotape), are used to provide access to visitors who are blind or have low vision. Docents or tour guides can be trained to employ audio description in their presentations. In film and television, description is typically delivered via a secondary audio track. In North America, Second audio program (SAP) is typically used to deliver audio description by television broadcasters. To promote accessibility, some countries (such as Canada and the United States) have implemented requirements for broadcasters to air specific quotas of programming containing audio description. The transition to "talkies" in the late 1920s resulted in a push to make the cinema accessible to the visually impaired. The New York Times documented the "first talking picture ever shown especially for the blind"—a 1929 screening of Bulldog Drummond attended by members of the New York Association for the Blind and New York League for the Hard of Hearing, which offered a live description for the visually-impaired portion of the audience. In the 1940s and 1950s, Radio Nacional de España aired live audio simulcasts of films from cinemas with descriptions, framing these as a form of radio drama before the advent of television.