Proximity sensors are devices that detect the presence or absence of an object within a certain range without physical contact. They are commonly used in various applications, such as smartphones, automated doors, and industrial machinery, to enhance functionality and safety. These sensors can operate using different technologies, including infrared, ultrasonic, and capacitive methods. When an object comes close to a proximity sensor, it triggers a response, such as turning on a light or activating a machine. This technology is essential in modern automation, helping to improve efficiency and reduce the risk of accidents in both commercial and residential settings.