This color is the brightest possible blue that can be reproduced on a computer screen, and is the color named blue in X11. It is one of the three primary colors used in the RGB color space, along with red and green. The three additive primaries in the RGB color system are the three colors of light chosen such as to provide the maximum gamut of colors that are capable of being represented on a computer or television set.
This color is also called color wheel blue. It is at 240 degrees on the HSV color wheel, also known as the RGB color wheel. It is a spectral color which lies at, or near, the short-wave (violet) end of the traditional "blue" and possibly was classified as "indigo" by Newton. Its complementary color is yellow.
The color defined as blue in the CMYK color system used in printing, also known as pigment blue, is the tone of blue that is achieved by mixing process (printer's) cyan and process (printer's) magenta in equal proportions.
The purpose of the CMYK color system is to provide the maximum possible gamut of color reproducible in printing by the use of only three primaries.
The color indicated is only approximate as the colors of printing inks may vary.
International Klein Blue (IKB) is a deep blue hue first mixed by the French artist Yves Klein. IKB's visual impact comes from its heavy reliance on ultramarine, as well as Klein's often thick and textured application of paint to canvas. There is a legend that Klein patented the color, but in reality he simply submitted a Soleau envelope and never progressed to the patent stage.
Savoy blue, or savoy azure, is a shade of saturation blue between peacock blue and periwinkle, lighter than peacock blue.
It owes its name to its being the color of the House of Savoy, a ruling dynasty in Italy from 1861 to 1946.
Having become a national color with the unification of Italy (1861), its use continued even after the birth of the Italian Republic (1946) with the name "Italian blue". An Italian-blue border was inserted on the edge of the Presidential Standard of Italy and the use of the blue scarf for the Italian Armed Forces' officers, for the presidents of the Italian provinces during the official ceremonies and of the blue jersey for Italian national sports teams it was also maintained in the Republican era.
Navy blue is a shade of the standard (h = 240°) blue. Navy blue got its name from the dark blue (contrasted with white) worn by sailors in the Royal Navy since 1748 (originally called marine blue before 1840) and subsequently adopted by other navies around the world.
The color defined as blue in the NCS or Natural Color System is an azure-like color shown at right (NCS 2060-B). The Natural Color System is a color system based on the four unique hues or psychological primary colors red, yellow, green, and blue. The NCS is based on the opponent process theory of vision.
The “Natural Color System” is widely used in Scandinavia.
NCS Blue can only be displayed approximately on a computer screen, as these spectral colors have been adjusted to fit into the sRGB gamut. In the 21st century, this hue is classified as an variation of azure that is on the border of cyan.
The Munsell color system is a color space that specifies colors based on three color dimensions: hue, value (lightness), and chroma (color purity), spaced uniformly (according to the logarithmic scale which governs human perception) in three dimensions in the Munsell color solid, which is shaped like an elongated oval at an angle. In order for all the colors to be spaced uniformly, it was found necessary to use a color wheel with five primary colors: red, yellow, green, blue, and purple.
Celtic blue is a shade of blue, also known as glas celtig in Welsh, or gorm ceilteach in both the Irish language and in Scottish Gaelic. Julius Caesar reported (in Commentarii de Bello Gallico) that the Britanni used to colour their bodies blue with vitrum, a word that means primarily "glass", but also the domestic name for the "woad" (Isatis tinctoria), besides the Gaulish loanword glastum (from Proto-Celtic *glastos "green"). The connection seems to be that both glass and the woad are "water-like" (lat. vitrum is from Proto-Indo-European *wed-ro- "water-like").
Spanish blue is the color that is called Azul (the Spanish word for "blue") in the Guía de coloraciones (Guide to colorations) by Rosa Gallego and Juan Carlos Sanz, a color dictionary published in 2005 that is widely popular in the Hispanophone realm.
Yale Blue is the dark azure color used in association with Yale University. The hue of Yale Blue is one of the two official colors of Indiana State University, the University of Mississippi, and Southern Methodist University.The official color "DCU Blue" of Dublin City University is very close to Yale Blue.
Yale Blue was also an official color of University of California, Berkeley, and Duke University.
Penn Blue is one of the official colors of the University of Pennsylvania, along with Penn Red. While the school colors were defined by 1910, university history points to earlier times when the colors may have been chosen, including a possible visit by George Washington to the University, where students used the color of his tunic to determine school colors or a track meet where Penn athletes declared that they would wear the colors "of the teams we beat," which would be those of both Harvard University and Yale University. Originally defined as the colors used on the American flag, the colors have since deviated.
Berkeley Blue is one of the official colors of the University of California, Berkeley, along with California Gold. Until 2007, the university had used Yale Blue in its place, given Berkeley's historical ties to Yale University, particularly in its founding. Berkeley's school colors are the originators for those of all the campuses in the University of California system, of which Berkeley is the oldest as its flagship.