Police cars are special cars that help keep us safe! They drive really fast because they need to help people who might be in trouble or to catch bad guys who break the rules.
When you see a police car with its flashing lights on, it means they are in a hurry to help someone. Other people in cars see those lights and move out of the way so the police can get there quickly. It’s like playing a game of tag, where the police have to catch the 'bad guys' and help everyone stay safe!