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, including automobiles for parking assistance and robotics for obstacle detection. These sensors are favored for their accuracy and ability to work in various environments, including outdoors and in the dark. They can detect a wide range of materials, such as water, plastic, and metal, making them versatile tools in industries like manufacturing and agriculture.