Okay kiddo, have you ever heard of something called a "crime?" It's when someone does something that is against the law and can get them into trouble. Well, sometimes these crimes are more serious than others. The really serious ones are called "felonies."
A felony is a type of crime that can get someone in a lot of trouble with the law. Usually, it's something like hurting someone else really badly, stealing something very valuable, or doing something that endangers a lot of people.
When someone is convicted of a felony, it means that they have been found guilty of committing a really serious crime. This can come with some pretty severe punishments, like going to jail for a long time or having to pay a lot of money.
So basically, committing a felony is a really big deal and can have serious consequences for the person who does it. It's important to always follow the law and make good choices.