Rubbernecking is when you are driving in a car and you see something interesting happening on the side of the road, like an accident or a car pulled over by a police officer. Your neck might naturally turn to look at what's happening, but this is not safe because it takes your focus off of driving.
Rubbernecking can cause more accidents because when people slow down to look, it creates a traffic jam, and other drivers might not be paying attention and could crash into the back of the slow-moving cars. It's important to keep your eyes on the road and not let your curiosity get the best of you so that you can keep yourself and others safe.