Editing & Post-Production
Subtitles
Also called: subs, subtitle track
In broadcast terms, subtitles assume the viewer can hear the audio and needs the words, usually because they are in a different language. Closed captions assume they cannot hear, so they also describe the door slam and the music cue. YouTube collapses the two under one subtitles and CC label, and its automatic track is really a caption track.
Uploading your own matters more than most creators expect. Automatic text mangles names, jargon and strong accents, and it gives you nothing to translate from. A clean track fixes the accuracy, opens the door to other languages, and serves the many people who watch with the sound off or the text on by preference.