Why is the Sky Blue?

Ever wondered why the sky is blue? Why not green or yellow? Inquisitive of knowing the science behind it, I stumbled upon some great resources online. Here is a summary of what I found:
The blue color of the sky is due to Rayleigh scattering. When light passes thorough the atmosphere it collides with the nitrogen and oxygen atoms. While most of the longer wavelengths just pass straight through, the shorter wavelengths like blue and violet are scattered more by this collision. This makes the sky to appear blue/violet. Since our eyes are more sensitive to blue than violet light we perceive the sky as blue. Cool huh? There is a mathematical explanation to this concept. Rayleigh scattering is inversely proportional to forth power of wavelength. This means blue with a shorter wavelength scatters more making the sky look blue.