See http://www.delphiki.com/webvtt/ for a description of Web VTT files
//initiate the captions
textTrack.init(HTML element to display captions, [Array of vtt captions file urls]);
//on ready event
textTrack.ready(function(){
//once all the vtt files are loaded and parsed
//do something else
});
//display the captions
textTrack.setCaption('url to caption file', timeMillisec);
//clear caption display
textTrack.clearCaption();
jQuery (this dependency could easily be removed)