The phenomenon responsible for rainbows is the refraction, dispersion, and reflection of light, particularly sunlight, in water droplets. When sunlight enters a water droplet, it bends (or refracts) due to a change in speed as it moves from air to the denser water. As the light exits the droplet, it is dispersed into its component colors—red, orange, yellow, green, blue, indigo, and violet. These colors then reflect off the inner surface of the droplet and emerge to form a circular arc that we perceive as a rainbow. Rainbows are typically seen when sunlight shines after rain, creating a beautiful display in the sky.