Ultrasonic sensors are devices that use sound waves to detect objects and measure distances. They emit high-frequency sound waves, which bounce off nearby objects and return to the sensor. By calculating the time it takes for the sound waves to return, the sensor can determine how far away the object is. These sensors are commonly used in various applications, such as automotive parking assistance, robotics, and industrial automation. They are valued for their accuracy and ability to work in different environmental conditions, making them suitable for both indoor and outdoor use.