Light sensors are devices that detect and measure light levels in the environment. They convert light energy into electrical signals, allowing them to respond to changes in brightness. Common types of light sensors include photodiodes, phototransistors, and light-dependent resistors (LDRs). These sensors are widely used in applications such as automatic lighting systems, cameras, and smartphones. Light sensors play a crucial role in various technologies by enabling automatic adjustments based on ambient light conditions. For example, they can dim or brighten lights in response to the time of day or the presence of natural light. This functionality helps save energy and enhances user experience in devices like smart home systems and outdoor lighting.