Why does the Audi A8 use a mild hybrid system?

I've noticed that the Audi A8 has been advertised as having a mild hybrid powertrain. What are the benefits of this system and how does it work?

The mild hybrid system used in the Audi A8 helps improve fuel efficiency and reduce emissions. It works by using a small electric motor to assist the combustion engine during acceleration and shut off the engine when coasting, saving fuel in the process.

The mild hybrid system in the Audi A8 also helps with the overall driving experience. The electric motor provides additional torque which improves acceleration and makes the drive smoother.

In addition to improving fuel efficiency and driving experience, the mild hybrid system in the Audi A8 also allows for smoother engine start-stop functionality and better regenerative braking.