LDR-Light Sensitive Resistor 5mm Photoresistor

The Light Dependent Resistor, abbreviated as LDR, is a type of photoresistor. A photoresistor is a class of electronic components that exhibit a change in resistance based on the intensity of light they are exposed to.
Constructed from the semiconductor material known as "cadmium sulfide" (CdS), the LDR has the unique ability to absorb light photons. This characteristic is what enables the change in resistance.