A very simple definition.
As you know, people who do not hear or have difficulties in this regard (I am here), have a service that most televisions offer that simply is to activate subtitles (initially served by Teletext).
And so they can watch the news with subtitles, or a series or any other program that offers that function.
The thing is, I imagine that in both languages the terms can be confusing because theoretically a subtitle can be seen / understood as a caption, or vice versa.
I explain. Both are graphical solutions for displaying text on the screen.
What differentiates them is, if anything, their function and technology used.
Namely: the label belongs to the image itself (the client cannot activate or deactivate it) and its function is to indicate who is presenting, or an explanatory text – by way of a title – on the subject they are talking about, etc …
The subtitle does not belong to the image itself (unless they have done it that way, I mean for example a film, documentary or whatever where, let’s say, it is shot in English – aimed at English speakers, so the audio is in that language- but it turns out that at some point there are conversations in Chinese (the audio is respected in Chinese and they add / integrate a text in English, as a subtitle) and the client can activate it or not (in the example above – temporary audio in Chinese, integrated subtitle ¿or label? in English, with the possibility of activating the subtitling – not integrated, of course- in Spanish) Its function is normally the translator.
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