Phosphorescence is a process where certain materials absorb light energy and then re-emit it over an extended period. This phenomenon occurs when electrons in the material are excited to a higher energy state and, after a delay, return to their original state, releasing light in the process. Unlike fluorescence, which emits light almost instantly, phosphorescent materials can glow for seconds to hours after the light source is removed. Common examples of phosphorescent materials include glow-in-the-dark paints and zinc sulfide or strontium aluminate compounds. These materials are often used in safety signs, toys, and decorative items, providing visibility in low-light conditions.