Read the newspaper, play games on your phone, and read to your children - all while sitting at the wheel.

The dream of self-driving cars is gradually getting closer, and accident researchers all over the world agree that widespread use of fully automated self-driving cars is likely to bring down the number of accidents and deaths on roads.

But what exactly are the different categories of car automation?

Many vehicles already on the road are partially automated and networked, and the trend is for the amount of automation to increase.

In order to better classify past, current, and future developments, the companies cooperating in the German Automotive Industry Association have developed a six-level system.

"This classification describes which tasks the vehicle performs with its assistance systems and which demands are made on the driver," explains Walter Niewoehner, from the German safety inspection agency Dekra.

Level 0: This corresponds to continuous driving without any actively intervening assistance systems. The driver is in complete directional control of the vehicle.

Level 1: Here the driver is supported by active systems that take over either the longitudinal or lateral guidance of the vehicle. An example of this would be in a proximity cruise control system that governs the speed and distance to the vehicle in front, while the driver still has control of the steering function in normal traffic. However, in an emergency, the driver can override the automatic controls by carrying out emergency braking, for example.

Level 2: This means the car is partially automated. In certain cases, the driver leaves the longitudinal and lateral guidance completely to the car and its assistance systems. However, you still have overall responsibility for everything.

"That means you have to constantly monitor the overall system and intervene immediately if circumstances require it," says Niewoehner.

Level 3: A highly automated system that permanently takes over longitudinal and lateral control and automatically recognises when the required environmental conditions or other prerequisites no longer apply.

It then prompts the driver to take over the driving. The driver no longer needs to constantly monitor such a system and can devote their attention to more demanding secondary activities.

"These require the system to alert the driver in enough time so they can safely take over," says the Dekra expert.

Level 4: Here the car basically drives itself completely in every conceivable traffic situation. The driver can even sleep while travelling, but must be able to take over the vehicle when requested to do so.

Level 5: The ultimate level of autonomous driving - the car drives completely independently of any human control in any situation and can even be designed without a steering wheel.

 - dpa