Blue is one of the three primary colours of pigments in painting,what's your color preference?
I personally love red. Why do you like blue?
Because whenever I look at the daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering.
Rayleigh scattering? What is that? I have never hear of this. 
Its the is the (dominantly) elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation
I see, what else do you know about the color blue?
Shades of blue
Varieties of the color blue may differ in hue, chroma (also called saturation, intensity, or colorfulness), or lightness (or value, tone, or brightness), or in two or three of these qualities. Variations in value are also called tints and shades, a tint being a blue or other hue mixed with white, a shade being mixed with black. A large selection of these various colors is shown below.
Tints of blue.
In this section, the term tint
Blue
Blue is one of the three primary colours of pigments in painting and traditional colour theory, as well as in the RGB colour model. It lies between violet and green on the spectrum of visible light. The eye perceives blue when observing light with a dominant wavelength between approximately 450 and 495 nanometres. Most blues contain a slight mixture of other colours; azure contains some green, while ultramarine contains some violet. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering.