A Light Dependent Resistor (LDR / Photoresistor) is a passive, light-sensitive electronic component whose electrical resistance decreases as ambient light intensity increases. Made from a semiconductor material such as Cadmium Sulfide (CdS), its surface features a distinctive serpentine conductive track. In complete darkness, the photoresistor exhibits a very high resistance (often in megohms), which drops to a few hundred ohms when exposed to bright light. Its two flexible through-hole leads allow seamless insertion into breadboards, perfboards, and sensor circuits.

This product is featured by Famephase Electronic Accessories as an essential, low-cost sensor component for automatic night lights, solar street light controls, light meters, and optical sensing DIY projects.