An emergency vehicle siren is a loud, attention-grabbing sound used by vehicles such as ambulances, fire trucks, and police cars to alert the public of their presence. The siren helps clear the way in traffic, allowing these vehicles to respond quickly to emergencies. These sirens typically produce a variety of tones and patterns, which can vary by region. The distinct sounds are designed to be easily recognizable, ensuring that drivers and pedestrians can hear them from a distance, promoting safety and swift passage during critical situations.