HTMLTrackElement: kind property
The kind property of the HTMLTrackElement interface represents the type of track, or how the text track is meant to be used. It reflects the <track> element's enumerated kind attribute.
If no kind is set, subtitles is used. If the attribute is not set to one of the valid enumerated values, it is invalid and metadata is used. Other valid values include captions, descriptions, and chapters.
Value
A string; lowercase captions, descriptions, chapters, subtitles or metadata.
Example
Given the following:
html
<track src="track.vtt" id="exampleTrack" />
We get the following results:
js
const trackElement = document.getElementById("exampleTrack");
// missing value
console.log(trackElement.kind); // "subtitles"
trackElement.kind = "INVALID";
// invalid value
console.log(trackElement.kind); // "metadata"
trackElement.kind = "CAPTIONS";
// valid value
console.log(trackElement.kind); // "captions"