Subtitles are designed for hearing users, as they only cover spoken text and do not include sound effects or other audio elements. SDH, on the other hand, are designed for those who are deaf or hard of hearing by including additional information, such as speaker tags, sound effects and other elements outside of the speech itself. Closed captions are required by law on all public broadcasts, as per FCC regulations, and are typically formatted as white text on a black background that can be positioned anywhere on the screen.
