Multiple video URLs let you link multiple videos to a single set of subtitles. Some example uses:
Two versions of the same video exist on Youtube. You do not want subtitle volunteers to duplicate their work, so you add both versions to the multiple URLs pane.
You put your video on Youtube, Vimeo and Dailymotion and you want the subtitles you make to work on all of those versions.
You want to provide different versions of a video to different browsers (HTML5/Ogg for free software users, or HTML5/h264 to iPad users). If you add these URLs, our embed code will automatically fall back to whatever format is necessary for the browser.
Tip: double check that there are no timing problems.