Chrominance is a big word that means the color of things on TV and videos.
Imagine you are drawing a picture with crayons. You have many colors to choose from, like red, yellow, blue, and green. When you color something with one of these colors, that is called its chrominance.
Now let's think about watching a movie on TV. You also see many colors, like the blue sky or a green grass. These colors are not made by crayons, but by tiny dots of light called pixels.
The part of the TV that controls these colors is called the chrominance. It makes sure the colors look the same on different TVs and screens.
So chrominance is just a fancy word that means the colors you see on TV or videos.