The HC-SR501 PIR Motion Sensor Module is a widely used and reliable infrared sensor designed to detect human body movement. It utilizes passive infrared (PIR) technology to sense changes in infrared radiation emitted by moving objects, especially humans.

This module features adjustable sensitivity and delay time, allowing users to customize detection range and output duration according to their application. It provides a digital HIGH/LOW output when motion is detected, making it easy to interface with Arduino, Raspberry Pi, and other microcontrollers.

The HC-SR501 is equipped with a Fresnel lens for improved detection and offers stable performance in various environments. It is commonly used in security systems, automatic lighting, and smart home automation.