Blue

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Color icon blue

Egyptian blue

Cobalt Blue

Blue is a color that is part of the visible spectrum, lying between violet and green. It is one of the three primary colors in the RGB color model, alongside red and green. The perception of blue is evoked by light having a spectrum dominated by energy with a wavelength of roughly 450–495 nanometres. Blue is considered a cool color in color theory, and it is often associated with calmness, stability, and serenity.

Etymology

The word "blue" comes from the Old French word bleu, which originated from the Old High German word blao, meaning "shining". The term has been used to describe colors since the 12th century.

Cultural Significance

Blue holds significant cultural, symbolic, and psychological meanings in various contexts. In many cultures, blue is associated with peace, trust, and loyalty. It is also the color most commonly associated with harmony, faithfulness, and confidence. In contrast, it can also symbolize sadness or melancholy, as in the phrase "feeling blue".

Religious and Mythological Associations

In religion and mythology, blue often represents the heavens or the divine. For example, in Hinduism, the god Krishna is depicted with blue skin. In Christianity, the Virgin Mary is often portrayed wearing blue clothing, symbolizing purity and virtue.

Political and Social Associations

Blue is also used in a political and social context, representing liberalism in many countries. It is the color of numerous national flags, symbolizing freedom and unity.

Science and Nature

In science, blue is one of the most interesting colors due to its rarity in nature. Few natural substances reflect blue light, which is why blue pigments and dyes were historically precious and expensive.

Astronomy

In astronomy, a blue star is a star that has a high surface temperature and a spectral type of O or B. Blue stars are among the most luminous and massive stars in the universe.

Biology

In biology, the blue coloration of some animals and plants is due to various factors, such as the Blue Morpho butterfly, which has microscopic structures on its wings that reflect blue light.

Art and Design

In art and design, blue is a color that has been used for centuries, from the rare and expensive ultramarine pigment used in the Renaissance to the modern use of synthetic blue dyes. It is a popular color in interior design, symbolizing tranquility and comfort.

Technology

In technology, blue lasers are a significant advancement, used in various applications including Blu-ray discs and medical devices. The development of blue LEDs was also a groundbreaking achievement, earning the inventors the Nobel Prize in Physics in 2014.

See Also

• Color psychology
• List of colors

Blue Resources
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