In 1913, Edison synchronized a phonograph to a movie. The sound was reproduced using a horn, with no amplification. The synchronisation mechanism used a pulley running from the projection box to the phonograph behind the movie screen. Thus began film sound. Since then, technology has advanced somewhat, leading to today's high quality, multichannel digital sound systems. A history of movie sound is presented, from the original sound on disc mechanisms to the present day. Some technical information on the various schemes used is provided, with emphasis being placed on SVA (stereo variable area) and the noise reduction systems required to achieve good performance from analog systems. The Dolby MP (surround) matrix is described, as well as its consumer counterparts, Dolby Surround and Dolby ProLogic. Finally, digital sound delivery systems are described. Lossy psychoacoustic compression by subband coding is explained, and competing digital systems are described.