Tags: Language.
The Movietone sound system is an optical sound-on-film method of recording sound for motion pictures that guarantees synchronization between sound and picture. It achieves this by recording the sound as a variable-density optical track on the same strip of film that records the pictures. Although sound films today use variable-area tracks any modern motion picture theater (excluding those that have transitioned to digital cinema) can play a Movietone film without modification to the projector.