Okay kiddo, have you ever watched a video on the TV? Well, high definition video is like that, but much much better!
You know how sometimes when you watch a video it looks a little blurry, or the colors don't look as bright or real as they do in real life? Well, high definition video helps fix that.
It uses special technology to make the video look clearer and cleaner, and the colors look brighter and more true-to-life. It's like you're actually there watching whatever is happening on the screen, instead of just watching a video of it.
But, in order to watch high definition video, you need to have special equipment. You need a TV that can play high definition videos, and a device that is able to stream or play the video in high definition.
So that's high definition video, it's like watching a really clear and pretty video that makes you feel like you're really there!