Transcription & Subtitle Glossary

Short, practical definitions of the terms you meet when you transcribe recordings or work with subtitles — with examples and what each one means in practice.

SRT file: An SRT file (SubRip Subtitle, .srt) is a plain-text subtitle file. Each subtitle is a numbered cue with a start and end time and one or two lines of text. Players and platforms show the text over the video at those times, and viewers can switch it on or off.
VTT file: A VTT file (WebVTT, .vtt) is the subtitle and caption format of web video. It is plain text like SRT, but starts with the line WEBVTT, writes milliseconds after a full stop and can carry styles, positions and speaker tags that browsers understand.
Open captions: Open captions are captions burned into the video itself, as part of the picture. They are always visible, look the same on every player and platform, and cannot be switched off — unlike closed captions, which come as a separate track the viewer can turn on or off.
SDH subtitles: SDH stands for Subtitles for the Deaf and Hard of Hearing. Besides the dialogue, SDH subtitles name off-screen speakers and describe sounds that matter — [door slams], [phone buzzing], [tense music] — so the video makes sense without audio. Streaming services label them, for example, English [SDH].
Speaker diarization: Speaker diarization is the step in speech recognition that works out who spoke when. It splits a recording into segments by voice and labels them Speaker 1, Speaker 2 and so on, so an interview or meeting transcript shows each person's turns instead of one block of text.
Verbatim transcription: Verbatim transcription writes down speech exactly as it was said: every um and uh, repeated words, false starts, stutters and often non-verbal sounds like [laughs]. Its opposite, clean verbatim, keeps the speaker's words and meaning but removes fillers and stumbles so the text reads smoothly.
Timecode: Timecode is a label for every frame of video, written as hours:minutes:seconds:frames — 01:02:03:12 is frame 12 of the third second. Editors use it to find the same moment in every copy of a project. Subtitle files usually count time in milliseconds instead, which is where mix-ups start.
Forced subtitles: Forced subtitles appear even when the viewer has subtitles turned off. They cover only what a viewer in the film's language would otherwise miss: dialogue in another language, signs, letters and on-screen text. Streaming services call them forced narrative subtitles.
Transcription conventions: Transcription conventions are the agreed rules for turning speech into text: how to mark speakers, pauses, overlapping talk, emphasis, laughter and words you cannot make out. A study or a project picks one set of conventions and applies it to every transcript, so that transcripts made by different people can be compared.
Dubbing script: A dubbing script is the translated dialogue of a film or video, rewritten so that each line can be spoken in the time the original line takes on screen. It lists every line with the character who says it and its in and out timecodes. The adapted text is what voice actors, or an AI voice, read in the studio.
Dubbing: Dubbing is replacing the speech in a film, series or video with new recorded speech, usually a translation into another language, so viewers hear the story in their own language instead of reading subtitles. The new lines are timed to the picture, and the music and sound effects of the original are kept.
Voice-over translation: Voice-over translation lays a spoken translation over the original audio, which stays audible at a lower volume underneath. Unlike dubbing, it does not try to replace the original voices or match lip movements: viewers hear that someone else is translating.
Voice cloning: Voice cloning is creating a synthetic voice that sounds like a specific real person, from recordings of their speech. The clone can then say new sentences the person never recorded, including in other languages, which is how dubbing tools keep a speaker’s own voice in a translation.