Nowadays, smart phone has been part of our life. We can see people lowing down their heads and playing smart phones all the time. When people are walking on the street, the traffic regulations are no longer their first concern. It is so dangerous for them to keep their attention on the phone. Dutch officers figured out a new rule to let people realize the traffic lights. On the ground, the traffic light can be seen. What a smart idea. When people are watching smart phones, they can see the lights, too. At the same time, we need to think about the problem that whether our life is controlled by the technology.