Phosphorescence is a type of photoluminescence related to the way certain materials absorb and re-emit light. When these materials, often called phosphors, are exposed to light, they store energy and release it slowly over time. This process allows them to glow even after the light source is removed. The glow from phosphorescent materials can last from a few seconds to several hours, depending on the specific substance and conditions. Common examples of phosphorescent materials include glow-in-the-dark toys and watch dials, which utilize this property to provide illumination in the dark.