What is the difference between the Audi A1 Petrol and Diesel engines?

I've been comparing the specs for the Audi A1 and noticed that there are both petrol and diesel options available. What are the main differences between these two types of engines? Is one more efficient than the other? And how does this affect the overall performance of the car?

The difference between petrol and diesel engines lies in their combustion processes. Petrol engines use a spark plug to ignite fuel and air mixture, while diesel engines use compression to ignite the fuel. This difference results in better fuel efficiency and torque for diesel engines, but petrol engines generally have better acceleration and power.