What is the difference between the Audi A1 30 TFSI and a 35 TDI S tronic?

I am contemplating between the Audi A1 30 TFSI and the 35 TDI S tronic models but I am unsure of what the main differences are. Can someone explain to me the key variations between the two? Thanks!

The main difference between these two models lies in their engine and transmission options. The A1 30 TFSI is equipped with a turbocharged gasoline engine and a 7-speed S tronic transmission, while the A1 35 TDI S tronic features a diesel engine and 6-speed S tronic transmission. In terms of performance, the TFSI model is quicker off the line and offers a smoother ride, while the TDI model provides better fuel efficiency and torque.