Photoelectric smoke alarms are devices designed to detect smoke and alert occupants of a potential fire. They use a light source and a sensor to identify smoke particles in the air. When smoke enters the alarm, it scatters the light, triggering the alarm to sound. These alarms are particularly effective at detecting smoldering fires, which produce more smoke before bursting into flames. Unlike ionization smoke alarms, which are better at detecting fast-flaming fires, photoelectric alarms provide a broader range of fire detection, making them a valuable safety tool in homes and buildings.