An airbag is like a special pillow that helps keep you safe when you are in a car. It lives inside your steering wheel or dashboard of your car, and it is there in case of a crash. If your car hits something, the airbag quickly blows up and comes out of the steering wheel or dashboard. The airbag helps to stop you from hitting your head hard on the steering wheel or dashboard if you're in a crash. That's why it's important to always wear your seatbelt so that you don't get hurt from the airbag or from flying out of the car if there is an accident.