White

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For other uses, see White (disambiguation).
White
— Color coordinates —
Hex triplet #FFFFFF
RGBa (r, g, b) (255, 255, 255)
HSV (h, s, v) (-°, 0%, 100%)
a: Normalized to [0–255] (byte)

White is the color of things that reflect light of all parts of the visible spectrum equally and are not dull (see grey).

The color (more accurately, it contains all the colors of the visible spectrum and is sometimes described as an achromatic color, like black) that has high brightness but zero hue. The impression of white light can be created by mixing (via a process called "additive mixing") appropriate intensities of the primary color spectrum: red, green and blue, but it must be noted that the illumination provided by this technique has significant differences from that produced by incandescence (see below).

In nature, the color white results when transparent fibers, particles, or droplets are in a transparent matrix of a substantially different refractive index. Examples include classic "white" substances such as sugar, foam, pure sand or snow, cotton, clouds, milk, etc. Crystal boundaries and imperfections can also make otherwise transparent materials white, as in the case of milky quartz or the microcrystalline structure of a seashell. This is also true for artificial paints and pigments, where the color white results when finely divided transparent material of a high refractive index is suspended in a contrasting binder. Typically paints contain calcium carbonate and/or synthetic rutile with no other pigments if a white color is desired.


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[edit] Shade

[edit] Paint

In painting, white can be created by reflecting ambient light from a white pigment, although the ambient light must be white light, or else the white pigment will appear the color of the light. White when mixed with black produces gray. To art students, the use of white can present particular problems, and there is at least one training course specializing in the use of white in art.

[edit] White light

Until Newton's work became accepted, most scientists believed that white was the fundamental color of light; and that other colors were formed only by adding something to light. Newton demonstrated this was not true by passing white light through a prism, then directing the individual colored beams through another prism. If the colors were added by the prism, the second prism should have added further colors to the single-colored beam. Since the single-colored beam remained a single color, Newton concluded that the prism merely separated the colors already present in the light. White light is the effect of combining the visible colors of light in equal proportions.

In the science of lighting, there is a continuum of colors of light that can be called "white". One set of colors that deserve this description are the colors emitted, via the process called incandescence, by a black body at various relatively-high temperatures. For example, the color of a black body at a temperature of 2848 kelvins matches that produced by domestic incandescent light bulbs. It is said that "the color temperature of such a light bulb is 2848 K". The white light used in theatre illumination has a color temperature of about 3200 K. Daylight has a nominal color temperature of 5400 K (called equal energy white), but can vary from a cool red up to a bluish 25,000 K. Not all black body radiation can be considered white light: the background radiation of the universe, to name an extreme example, is only a few kelvins and is quite invisible.

[edit] Standard whites

Standard whites are often defined with reference to the International Commission on Illumination's (CIE's) chromaticity diagram. These are the D series of standard illuminants. Illuminant D65, originally corresponding to a color temperature of 6,500 K, is taken to represent standard daylight.

[edit] Computers

Computer displays often have a color temperature control, allowing the user to select the color temperature (usually from a small set of fixed values) of the light emitted when the computer produces the electrical signal corresponding to "white". The RGB coordinates of white are 255 255 255.

[edit] Usage, symbolism, colloquial expressions

In general, in the Western world, white is associated with a positive connotation. Activists and race theorists consider this association a result of Western racism. Many negative expressions with "black" have an equivalent positive expression with "white". For example, white hat describes a person who is ethically opposed to the abuse of computer systems, in contrast with a black hat, a person who abuses computer systems.

White has also many other meanings:

  • White is commonly the colour of snow and ice, though these often have a blue tint, even when not contaminated with other things that may change their color.
  • The term white is often used in the West to denote the race of so-called lighter skin Caucasoids people of European descent with pale to white skin color, whose skin color actually ranges from pink to pale brown. For more details, see Whites.
  • White noise, in acoustics, is a sibilant sound that is often a nuisance, although it can also be deliberately created for test purposes.
  • Whitewash, figuratively, means an attempt to obscure the truth by issuing a blanket of lies. See propaganda. Also, it refers to the action of burying or shoving someone's face into the snow, as a form of bullying, or harassment(generally).
  • Whiteout is a weather condition in which visibility is reduced and surface definition lost in snowy environments.
  • In ancient China, white was the symbol of West and Metal, one of the main five colors.
  • In English heraldry, white or silver (color) signified brightness, purity, virtue, and innocence. (The American Girls Handy Book, p. 369)
  • White is the traditional color of bridal dress in both western (European) and Japanese weddings. In Western weddings, a white dress is thought to be symbolic of purity (the bride has not engaged in pre-marital sex). This is also said to be the symbolism of the veil.
  • A white paper can be an authoritative report on a major issue, as by a team of experts; a government report outlining policy; or a short treatise whose purpose is to educate industry customers. It is called white paper because it was originally bound in white.
White Ribbon
Enlarge
White Ribbon
  • To "show the white feather" is to display cowardice. In cockfighting, a white feather in the tail is considered a mark of inferior breeding. In Victorian England a purported coward would be presented with a white feather.
  • White has also become a prominent color depicting technology and the future in the 21st Century, most likely resulting from the heavy influence and increasingly widespread appeal of Apple Computer's products such as the Macintosh and the iPod.
  • Butterflies of subfamily Pierinae of family Pieridae are commonly referred to as Whites, and the term forms part of many of the butterflies of this group, for example, Bath White.

[edit] See also

Web colors black silver gray white red maroon purple fuchsia green lime olive yellow orange blue navy teal aqua
                                 
  Shades of white  
White Cream Cosmic latte Ivory Magnolia Old Lace Seashell
             


[edit] External links