Retinal is a light-sensitive molecule found in the retina of the eye, crucial for vision. It is derived from vitamin A and plays a key role in the process of converting light into electrical signals, which are then sent to the brain. This conversion is essential for our ability to see in different lighting conditions. When light hits retinal, it changes shape, triggering a series of biochemical reactions in the photoreceptor cells of the retina. This process ultimately leads to the perception of images. Without retinal, our vision would be severely impaired, highlighting its importance in the visual system.