A photoresistor, also known as a light-dependent resistor (LDR), is an electronic component that changes its resistance based on the amount of light it receives. When exposed to light, the resistance decreases, allowing more electric current to flow. Conversely, in darkness, the resistance increases, reducing the current. This property makes photoresistors useful in various applications, such as light sensors and automatic lighting systems. These components are commonly made from semiconductor materials, which are sensitive to light. Photoresistors are often used in devices like solar garden lights, streetlights, and camera exposure meters to help control lighting based on environmental conditions.