Okay kiddo, do you know how sometimes things can go wrong or not work as well as they should? That's where corrective and preventative action comes in.
Let's say you have a toy that keeps breaking. If you just keep fixing it every time it breaks, that's called corrective action. You're fixing the problem after it's already happened.
But what if you don't want your toy to keep breaking? That's where preventative action comes in. You would try to figure out why the toy keeps breaking and then do something to stop it from happening in the future, like using stronger materials or changing the way you play with the toy.
In bigger situations, like at work or in a factory, people also use corrective and preventative action. If something isn't working right, they can fix it (corrective action) or figure out how to stop it from happening again in the future (preventative action).
So to sum it up, corrective action is fixing a problem after it happens and preventative action is trying to stop the problem from happening in the first place. Like fixing a toy or figuring out how to keep it from breaking again.