A motion sensor, also known as a motion detector, is an electronic device that detects nearby humans or objects using sensors. Motion sensors, unlike many other types of sensors, are typically embedded systems comprised of three major components: a sensor unit, an embedded computer, and hardware (or consisting of mechanical components). When the motion sensor detects a moving object, the system performs data analysis and data comparison and sends an alarm message to your mobile device via the Internet, letting you know right away if there is a security issue in the detection area. Furthermore, if you subscribe to a merchant's monitoring service, you can set up motion sensors to send alerts to the monitoring team automatically.