PIR Motion Sensor works on infrared light to detect whether a object has in or out. This is also known as energy saver because it sense the object and after turn on or off switches of premises. The main advantage of this sensor is small, inexpensive and easy to use and also consume low power. That's why mostly used in home applicance and gadget. 

There are many application of PIR Motion Sensor like

• Basements
• Covered parking area 
• Shopping malls 
• Offices / Conference Room 
• For garden lights and Lift Lobby