A proximity sensor (often shortened to proxy sensor) is an electronic sensor that can detect the presence of an object without physical contact.  By using a proxy sensor, it assists with sensing objects that are nearby, it provides a signal to a machine control system when the object is detected and it is often used to replace mechanical switches for simplicity.  The proxy sensor is typically used in machine safety, automation, vehicles or industrial equipment. In short the proxy sensor is a non- contact detector that tells a system when something is nearby enabling machines to be safer, faster and more reliable.