A Passive Infrared (PIR) is an electronic device used to detect motion by measuring infrared (IR) radiation emitted by objects in its field of view. The sensor is made up of two slots, each sensitive to infrared radiation. When a warm object (like a person) enters the field of view, it creates a difference in the infrared levels between the two slots, causing the sensor to trigger. The PIR sensor doesn't detect specific objects but rather changes in infrared levels caused by movement. PIR sensor

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