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?
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.
Green
Green is the color between blue and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a combination of yellow and blue, or yellow and cyan; in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. By far