Natural light, such as sunlight or moonlight, is composed of a continuous spectrum of colors rather than a finite number. This continuous spectrum of colors forms what we perceive as white light.
When sunlight passes through a prism or water droplets in the atmosphere (as in a rainbow), it gets dispersed into its component colors, creating a rainbow or a spectrum. This spectrum consists of various wavelengths of light, ranging from shorter wavelengths (violet and blue) to longer wavelengths (green, yellow, orange, and red). These colors blend seamlessly into each other, resulting in the perception of white light.
The reason for this continuous spectrum is that sunlight is a combination of different colors of light emitted by the sun. Each color corresponds to a specific wavelength, and together they form the full spectrum of visible light.
While the human eye can distinguish different colors within the visible spectrum, it's worth noting that there are many more colors in the electromagnetic spectrum beyond what we can see, such as ultraviolet and infrared, which are also present in natural light.