On-screen text transcribing spoken dialogue in a video — required for sound-off viewing on every modern social-video feed.
Subtitles are the burned-in or rendered text that transcribes what a speaker says in a video. They're functionally identical to closed captions in most modern usage (the distinction — subtitles for translation, captions for accessibility — has mostly collapsed). Every major social-video feed autoplays muted: Reels, TikTok, Shorts, X video, LinkedIn video. Without subtitles, 80–90% of viewers scroll past before unmuting.
Two technical flavors. Burned-in subtitles are baked into the video pixels — they ship with every cross-post and can't be turned off. Rendered subtitles (the YouTube CC track, the IG auto-caption toggle) are a separate text layer the viewer can hide. For short-form, burned-in is the standard because it survives cross-posting and looks consistent across platforms.
Styling matters more than people think. Color, font, position, animation timing, and box vs. no-box all affect retention. Submagic and Captions popularized the "word-by-word highlight" style; Kompozy ships 7 caption presets in libass-burned format that match the dominant short-form styles.