Okay kiddo, let me put it this way - have you ever colored a picture with crayons or colored markers? Just like how you try to make sure the colors don't go outside the lines, photographers use something called the "zone system" to make sure the colors in their pictures look just right too.
The zone system is basically a way to measure the brightness of different parts of a photo. Imagine you're looking at a page in a coloring book with different shapes on it. Some shapes might be really light and some might be really dark, right? That's kind of like how a photo has different areas of lightness and darkness.
With the zone system, photographers divide up these different areas of lightness and darkness into "zones" from 0 to 10. Zone 0 is completely black with no detail, while Zone 10 is pure white with no detail. Most of the interesting stuff in a photo usually happens in the middle zones - zones 3-7.
So, by using the zone system, photographers can figure out which zones they want to prioritize in their shot. Let's say they're taking a picture of a sunset - they might want the sun to be in Zone 8 or 9, but they also want to make sure the shadows in the foreground aren't completely black (Zone 0).
By paying attention to the different zones in their picture, photographers can get a more balanced and visually pleasing shot that captures all the details they want to show. And just like how you might use different colors on a coloring page to create a picture, photographers can use different settings on their camera to adjust the brightness of different zones and create their desired effect.