SDH
Subtitles for the Deaf and Hard of Hearing — same-language captions that include non-dialogue audio cues like [APPLAUSE] or [DOOR SLAMS].
SDH is the streaming-era equivalent of traditional closed captions: same-language text rendering of dialogue, plus audio cues that convey the parts of the soundtrack hearing audiences pick up on instinctively (sound effects, music descriptions, speaker identification).
Streaming platforms often label this 'English (SDH)' or 'English [CC]' to distinguish from translation-only subtitles ('English' alone).
For live events, the live-captioning equivalent of SDH is captions that label speakers and include any non-speech audio relevant to understanding (audience laughter, applause, background sounds during demos). Most modern captioning platforms support this via speaker labels and explicit audio cue annotation.