On the other hand, light is a fundamental concept in physics and refers to electromagnetic radiation that is visible to the human eye. It is composed of photons, which are particles that carry energy. Light can be described in terms of its properties such as intensity, wavelength, and frequency. Different wavelengths of light correspond to different colors in the visible spectrum.
If you can provide more context or clarify what you mean by "darkeners," I'll be happy to try and assist you further.