World practice has classified driverless technology to six levels. It ranges from L0 and L5.

Most of the world's mainstream automotive products are L3 level. The L3 smart car has numerous smart technologies. It can operate in most cases without human intervention. Yet it needs people to brake and steer.

Level 0 means no autopilot. Most cars on the road today are level 0. It needs manual control.

Level 1 means driver assistance. This is the lowest level of automated cars. The vehicle only has a driver assistance system. It is separate automated driver assistance system. Such as steering assist, acceleration assist, adaptive cruise control.

The adaptive cruise control system is powerful. It enables the vehicle to keep a safe distance from other vehicles. The driver is only responsible for monitoring steering and braking.

Level 2 is partially autonomous

This class has advanced Driver Assistance Systems (ADAS). The vehicle can steer, accelerate, decelerate autonomously.

The vehicle at level 3 is conditional autonomous driving. We can see from a technical point of view. Level 2 to level 3 is a major qualitative leap. But from the driver's point of view, the difference is not so obvious.

Level 3 driverless cars are capable of "environmental detection". The vehicle can make its own judgments and decisions. These depend on the information. This is automatically determined when a car accelerates past a slow-moving vehicle. It's worth remembering, though, that this level still requires human control of the vehicle.

Drivers must be alert when driving a vehicle of this class. Once the system is unable to perform the task, the driver should immediately take control of the vehicle.

Vehicle at level 4 is more autonomous. This is the key difference between level 3 and level 4 automation. Sometimes an accident or system failure occurs while driving. The level 4 self-driving cars can intervene on its own.

In most cases, these cars do not require human intervention. Level 4 vehicles can operate in driverless mode. The driver can choose to manually control the vehicle.

Level 5 means total autonomous driving. There is no need for human attention when driving a car at this level. At some level it automatically exempts the "dynamic driving task".

Level 5 need no steering wheel or acceleration/brake pedals. Cars of this class will not be restricted by geographical fence. It has enough power to go anywhere. And perform any controls that an experienced human pilot can perform.