Colored light can be composed of photons with a discrete wavelength or set of wavelengths that cover a range. Use Wolfram|Alpha to find the properties of these colors, such as their effective temperature, wavelength ranges and even what bioluminescent creatures emit them. Compare different colors or identify a color by its wavelength.
Examine the properties of visible light, including how it is absorbed and emitted and how different spectral colors compare.
Find colors corresponding to particular wavelengths and frequencies.