How does the Audi A7's hybrid engine contribute to its efficiency?

I am considering purchasing the Audi A7, but I'm wondering about the efficiency of its hybrid engine. How does the hybrid system work and what benefits does it provide in terms of fuel economy?

The Audi A7's hybrid engine combines a traditional gas engine with an electric motor, allowing it to use both power sources to maximize efficiency. It also has a regenerative braking system, which captures energy while braking and stores it in the battery for later use.