The "Triangle of Light" is a concept in the field of optics that describes the relationship between three key elements: light source, object, and observer. This triangle illustrates how light travels from a source, interacts with an object, and reaches the observer's eyes, allowing them to perceive the object. In practical applications, the Triangle of Light is essential for understanding photography and visual arts. It helps artists and photographers manipulate light to create desired effects, enhancing the overall composition and mood of their work. By mastering this triangle, creators can effectively convey their intended message through visual media.