Part 3/10:
Central to understanding these devices is recognizing the photoresistor, also known as a light-dependent resistor (LDR). This component changes its electrical resistance based on light exposure; more light results in lower resistance, facilitating easier current flow. Such behavior is quite the opposite of what's desired in many light-controlling applications. For instance, a standard nightlight should illuminate in darkness, meaning it requires a clever circuit design to counteract the inherent behavior of the photoresistor.