What is the difference between the Audi A8 TFSI and TDI models?

I am in the market for a new Audi A8, but I am having trouble understanding the difference between the TFSI and TDI models. Can someone break it down for me?

The main difference between the TFSI and TDI models is the type of engine used. TFSI stands for "Turbocharged Fuel Stratified Injection" and uses a gasoline engine, while TDI stands for "Turbocharged Direct Injection" and uses a diesel engine.

In terms of performance, TFSI models tend to have a higher horsepower and torque compared to TDI models, making them better for speed and acceleration. TDI models, on the other hand, have better fuel efficiency and are more suited for long-distance driving.