What is the function of the oxygen sensor in an Audi 80?

I'm curious about the purpose and importance of the oxygen sensor in my Audi 80. Can someone explain its function in a clear and concise way?

The oxygen sensor in your Audi 80 is responsible for measuring the amount of oxygen in the exhaust gases and providing this information to the engine control unit.

Without a properly functioning oxygen sensor, your car's fuel-to-air ratio will be inaccurate, leading to decreased performance and potential damage to the engine.

It's important to regularly check and replace your oxygen sensor as an old or faulty one can negatively impact your car's fuel efficiency and emissions.