What is Car Driverless System? How to rank them?

The American Highway Traffic Safety Commission (NHTSA) divides driverless technology into five levels

Level 0: the driver has 100% control, and the vehicle does not have any auxiliary equipment of safety system. At present, most vehicles belong to this level;
Level 1: vehicles have single or multiple electronic control systems with independent functions, such as automatic emergency braking system. Most new vehicles in the future belong to this level;
Level 2: at least two controls can be automated, such as the combination of active headway control cruise system and lane maintenance system;
Level 3: the vehicle has the functions of automatic obstacle avoidance, self guidance and active control, but the driver still has the control right;
Level 4: the vehicle is fully automatic. The user only needs to give relevant information, such as destination, route, etc. the vehicle cannot be changed to manual driving at will.