the color blue is very pretty. what can you tell me about it
Well, it is one of the primary colors in painting and is part of the RGB color model as well.
yeah nice. very needed color. anything else?
It lies between violet and green on the spectrum of visible light - I guess that's why you always see it in rainbow.
yup. always. anything cool a lot of people dont know about the color?
The sky and the deep sea are not really blue!  They only appear that way because of an optical effect.
what optical effect is that?
It's called Rayleigh scattering actually