Monochromatic light is electromagnetic radiation that consists of a single wavelength or a very narrow range of wavelengths. This means that monochromatic light is composed of only one color or hue. While theoretically, monochromatic light has precisely one wavelength, in practice, it is represented by a small bandwidth of wavelengths. To achieve monochromatic light, it can be isolated from polychromatic light using a device called a monochromator. A monochromator is designed to separate light into its different wavelengths and allows only a specific wavelength or a narrow range of wavelengths to pass through, effectively isolating the monochromatic light.