Why does the Audi A8 come equipped with a 48-volt hybrid system?

I've noticed that many newer Audi A8 models have a 48-volt hybrid system. What is this technology and how does it benefit the car?

The 48-volt hybrid system in the Audi A8 not only helps improve fuel efficiency, but also allows for the use of auxiliary systems such as air-conditioning and electric power steering without draining the main engine.

The 48-volt hybrid system also provides a smoother start-stop function, eliminating any jerking movements when the car comes to a stop and starts again.

The 48-volt hybrid system also enables regenerative braking, where energy from braking is captured and stored to power the car's electrical systems, further improving efficiency.