PLR Videos, are videos that have Private Label Rights that you can use them to do so may things, rebrand the videos as your own, you can post them on your website to drive more traffic to your website, you can even post them on your YouTube channel to give your subscribers great content to learn from.
Most of the PLR videos are MP4 format. Another great idea is to use the PLR videos to build your email list, or use the videos to setup an eLearning membership to teach your members so many different things.
One thing I recommend, just have fun learning different ways to use these PLR videos to help grow your business.