The <track> HTML element is used as a child of the media elements,
<audio> and <video>. It lets you specify timed text tracks (or time-based data),
for example to automatically handle subtitles.
e.g.
<video controls
src="/media/cc0-videos/friday.mp4">
<track default
kind="captions"
srclang="en"
src="/media/examples/friday.vtt" />
Sorry, your browser doesn't support embedded videos.
</video>