About blue
Blue is one of the three primary colours in the RYB colour model, as well as in the RGB (additive) colour model. It lies between violet and cyan 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. An optical effect called Tyndall effect explains blue eyes. Distant objects appear more blue because of another optical effect called aerial perspective.

Blue

body of water
body of water
blue and white striped textile
blue and white striped textile
blue Work Harder neon signage
blue Work Harder neon signage
round black metal table with chairs
round black metal table with chairs
blue wall bricks
blue wall bricks
white umbrella on ceiling
white umbrella on ceiling
portrait photography of yellow petaled flower
portrait photography of yellow petaled flower
white Ferris wheel under clear sky during daytime
white Ferris wheel under clear sky during daytime
mountain covering with clouds
mountain covering with clouds
jellyfish under water photo
jellyfish under water photo
body of water
body of water
mountains covered with fog
mountains covered with fog
low angle photography of white and teal painted building
low angle photography of white and teal painted building
blue fluid painting
blue fluid painting
blue and black digital wallpaper
blue and black digital wallpaper
body of water photograph
body of water photograph