What is the difference between a four-cylinder and a six-cylinder engine in an Audi A6?

I've been looking at Audi A6 models and noticed they have different engine options. What separates a four-cylinder from a six-cylinder engine in terms of performance and fuel efficiency?

The main difference between a four-cylinder and a six-cylinder engine in an Audi A6 is the number of cylinders and their corresponding power output. Four-cylinder engines are typically more fuel-efficient and better for everyday driving, while six-cylinder engines offer more power and better performance.