A motion sensor is a device that detects physical movement within a given area. In a household setup, a motion sensor is mainly used for security, turning on smart lights, and as an integral part of a motion sensor-based automation system. Using a motion sensor, detecting stationary gas or people becomes more efficient. Motion sensors scan the area to identify specific processes as changes with in it. Below indicates the most common forms of motion sensor technology: Passive Infrared (PIR) motion sensors: Recognize heat emitted from the human body. Microwave motion sensors: Use microwave pulses to identify motion. Dual-technology motion sensors: Combine multiple techniques to decrease false alarms. Residential and commercial buildings, factories, and warehouses are all examples of places where a motion sensor is applicable. For example, a motion sensor can be used to automatically switch on lights when someone enters a room, activate certain alarms for unexpected movement in certain zones, or even monitor employee movements within an office setting using a motion sensor system. With the introduction of smart technology, the motion sensor is now easier to obtain because it is more advanced, reliable, cheaper, and more energy efficient. For a household, office, or industrial premises, automation and security systems require a motion sensor for effective operation.