Glow, or radiance, refers to the emission of light or brightness from an object. This phenomenon can occur in various forms, such as the soft light emitted by a candle or the intense shine of the sun. Radiance is often associated with warmth and energy, making it a key concept in fields like physics and photography. In nature, glow can be observed in phenomena like bioluminescence, where living organisms, such as certain types of jellyfish and fireflies, produce light. Additionally, glow-in-the-dark materials absorb light and re-emit it, creating a luminous effect in the dark. This property is utilized in various applications, from toys to safety signs.