What is the difference between Audi A6 and Audi A6 Avant?

I am considering buying a new Audi A6 model, but I am confused about the differences between the A6 sedan and the A6 Avant. Can anyone explain the specifics of each model so I can make an informed decision?

The Audi A6 is a sedan, while the Audi A6 Avant is a wagon. This means the A6 Avant has a larger cargo capacity and more interior space compared to the A6 sedan.

The Audi A6 Avant has the same engine options as the A6 sedan, but it also comes with Audi's signature Quattro all-wheel drive system as standard.