What is the purpose of Audi A1's start-stop system?

I am considering the purchase of an Audi A1 and I noticed it has a start-stop system. What does this feature do and how does it benefit the vehicle?

The start-stop system in Audi A1 is designed to automatically turn off the engine when the car is stationary, such as at a red light or in heavy traffic. This reduces fuel consumption and emissions, making the vehicle more environmentally friendly.

When the start-stop system is engaged, the engine will restart when the driver releases the brake pedal or engages the clutch. This helps to improve fuel efficiency and reduce wear and tear on the engine components.

One important thing to note about the start-stop system is that it can be turned off if desired. However, keeping it on can greatly improve the overall fuel efficiency of the Audi A1, especially in urban driving conditions.