blue

Blue is one of the primary colors of light, meaning it cannot be created by mixing other colors. It has a short wavelength within the visible spectrum, roughly between 450 and 495 nanometers. Blue appears in the natural world in objects like the sky, oceans, and many flowers. Our eyes perceive blue through specialized cells in the retina called cones, which detect different wavelengths. The color is often associated with calmness, trust, and stability in human culture. In art and design, blue can evoke feelings of serenity and dependability, making it a popular choice for various uses.