Blue wiki:
>For other uses, see Blue (disambiguation) Blue is one of the three primary additive colors; blue light has the shortest wavelength range (about 420-490 nanometers) of the three additive primary colors. The English language commonly uses "blue" to refer to any color from blue to cyan.An example of a blue color in the RGB color space has intensities [0, 0, 255] on a 0 to 255 scale. Blue is the complement of yellow. For this reason, blue 80A filters are used to correct for the excessive redness of tungsten lighting in color photography.Many languages do not have separate terms for blue and green, and in the Swedish language, blå, the modern word for blue, was used to describe black until the early 20th century. The modern English word blue comes from the Middle English, where it began to be used along with bleu, an Old French word of Germanic origin (possibly Old High German blao, "shining"). A Scots and Scottish English word for "blue" is blae, from the Middle English bla ("dark blue", from the Old English blæd).
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Rainbow wiki:
>For other uses, see Rainbow (disambiguation). A rainbow is an optical and meteorological phenomenon that causes a nearly continuous spectrum of light to appear in the sky when the sun shines onto falling rain. It is a multicoloured arc with red on the outside and violet on the inside. The full sequence of colours is most commonly cited as red, orange, yellow, green, blue, indigo, and violet, though it is important to note that this is an inconsistent list; all primary and secondary colours are present in some form, but only one tertiary. It is commonly thought that indigo was included due to the different religious connotations of the numbers six and seven at the time of Isaac Newton's work on light, despite its lack of scientific significance and the poor ability of humans to distinguish colours in the blue portion of the visual spectrum.
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