The levels of autonomous driving :
Level 1: The first level of autonomy means the driver remains in control of the car the entire time. Steering and acceleration can be controlled by the car. These systems are already on sale and include self-parking and lane assist.
Level 2: These require drivers to pay attention to their surroundings and be prepared to take control of the vehicle in specific situations. Drivers have to keep their hands on the wheel just in case, too. Tesla Autopilot currently displays this level.
Level 3: These cars can make decisions for themselves without the need for driver inputs in certain situations. The Audi A8 can offer this technology - regulation permitting - with the ability to drive itself up to 37mph and goes on sale next year.
Level 4: These are true driverless cars that can navigate without any driver help and can independently indicate, brake and steer. These won't be on sale until 2021 at the earliest.
Level 5: The end goal is a car that doesn't need a driver at all - there might not even be pedals or a steering wheel. Google is currently developing an example of this with its Waymo project.
How it all started :
Header image courtesy of The Internet of Things Institute : www.ioti.com