The terms ‘caption’ and ‘subtitle’ are often used rather interchangeably. Each is a transcription of an audio or video recording that displays the spoken language as words on a screen.
This serves as an excellent tool to make recorded media more accessible to viewers in various circumstances. For example, it is well known that many people view online videos without sound, meaning they read the text on their device because they don’t want to disturb others nearby, or have physical hearing impairments.
In fact, “more than 100 empirical studies document that captioning a video improves comprehension of, attention to, and memory for the video. Captions are particularly beneficial for persons watching videos in their non-native language, for children and adults learning to read, and for persons who are D/deaf or hard of hearing.” (Gernsbacher, 2015)
By creating the transcription of the words spoken (and/or displayed on screen as graphics or titles) in their original language, this transcription can then be used to generate a localisation (translation) to appeal to many more audiences from different international markets.
The transcription could be generated as a single block of text, typical of written prose. But for the purpose of joining the text with certain images on a screen, it is necessary to generate coordinated time code. This is where a transcription becomes much more sophisticated, requiring professional software and services.
When we look more closely at the different potential consumers of video and audio content, there are subtle and important differences between captions and subtitles.
Similarities between captions and subtitles
Each is a text file accompanied by time code for synchronization to media. The most common format is SRT.
At a minimum, the text includes a transcription of what is being spoken. Text may also include on-screen text for subsequent translation (localization).
Differences between captions and subtitles
Subtitles generally only include a transcription of what is being spoken in the video or audio recording. These are often translated into various languages.
Captions can include other elements that describe sounds and music (for the hearing impaired) and can be toggled on and off (closed captions). Of course, captions can also be translated.
There are very many more detailed differences and options when configuring captions and subtitles, and many sources to learn about these differences.
Important considerations when ordering subtitling or captioning services
Is there existing on-screen text that needs to be included in the transcription for the purpose of translation?
Will the subtitles/captions cover up existing text (such as names and titles of speakers)? In this case, there may need to be another step involving specific placement of a caption on the screen.
Should the transcription include indications of other sounds (such as music) for hearing-impaired viewers?
Subtitling and captioning services are an excellent way to add to the value of your media content. It makes vastly more accessible to a much wider audience. It may also improve to increase the comprehension of viewers, even if they might otherwise understand the original language, as many people are more visual that aural learners.