Not too long ago YouTube adopted 4K content and then 360 video, now they’ve finally added HDR videos to their list of supported content so you’ll be able to watch said enabled videos.
High dynamic range, or HDR is a process that allows videos to have more detail in shadows or areas of extreme brightness, allowing you enjoy videos that look more like how you view the real world.
You’ll be able to upload any video with HDR to YouTube, though to watch it you will need a display capable of handling HDR. Basically you need something that goes over 1000 nits of brightness, and most mobile phones run at about 500-600 nits. That basically means you can’t enjoy HDR on your laptop, smartphone or a tablet, which means you’re likely only going to get to watch these new videos on your TV.
UHD and SUHD TVs released this year should be able to play the HDR videos later this year, though Chromecast Ultra is the only set-top box that has been confirmed to be able to playback said videos at the moment.