Levels of automation
Vehicle automation is defined into five levels. The higher the level, the more automated the vehicle is. Here are the five levels of automation, according to the Society of Automotive Engineers:
The human driver does everything.
An automated system on the vehicle can sometimes assist the human driver to conduct some parts of the driving task; e.g., existing features such as adaptive cruise control, automated parking systems and lane keeping assistance systems.
An automated system on the vehicle can actually conduct some parts of the driving task, while the human continues to monitor the driving environment and performs the rest of the driving task; e.g., Driver may have hands off the steering wheel and pedals at the same time, but is required to monitor and take control if needed.
An automated system can both actually conduct some parts of the driving task and monitor the driving environment in some instances, but the human driver must be ready to take back control when the automated system requests it.
An automated system can conduct the driving task and monitor the driving environment — and the human need not take back control. But the automated system can operate only in certain environments and under certain conditions.
The automated system can perform all driving tasks, under all conditions that a human driver could perform them.