Criminal law is like when grown-ups have rules that they have to follow or else they get in trouble with the police. In Singapore, there are rules that everyone must follow so that everyone can be safe and happy.
These rules are called laws, and if someone breaks these rules, they might have to go to court and get punished. Punishments can be things like going to jail, paying money, or doing community service.
Some common examples of rules that are enforced in Singapore's criminal law are stealing, hurting other people, and causing damage to property. These things are all very bad because they can hurt someone or make them sad.
So, it's important to remember to follow the rules and not break the law. If you see someone who is breaking the law, it's important to tell a grown-up or the police so they can help make things right again.