Technology giant Google is teaching its self-driving cars to honk at other motorists, as well as humming at pedestrians to let them know that they are approaching.
However, Google is making sure the cars are "polite, considerate and only honk when it makes driving safer for everyone."
The cars are also being taught the difference between false alarms and tricky situations, and to understand when cars are facing different directions.
Google shared in a monthly report: "At first, we only played the horn inside the vehicle so we wouldn't confuse others on the road with a wayward beep.
"Each time our cars sound the horn, our test drivers take note whether the beep was appropriate, and this feedback helps our engineering team refine our software further.
"As our honking algorithms improved, we've begun broadcasting our car horn to the world."
The car will also differentiate between separate beep-worthy incidents. For example, if a car was slowly reversing towards the Google vehicle, the latter would emit two small beeps to make the driver aware. However, should it detect that a more serious manoeuvre was taking place, it would emit a much louder noise.
On top of this, the car will emit a hum to make pedestrians aware that it is approaching. The firm said: "Our prototype mimics the sound characteristics of traditional cars, such as increasing in pitch when it accelerates and decreasing the pitch when it decelerates."