White

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For other uses, see White (disambiguation).
White
 
Color coordinates
Hex triplet #FFFFFF
RGB (r, g, b) (255, 255, 255)
CMYK (c, m, y, k) N (0, 0, 0, 0)
HSV (h, s, v) (0°, 0%, 100%)
  N: Normalised to [ 0–255 ] (changing to [0–100])

White is a color (more accurately it contains all the colors of the visible spectrum and is sometimes described as an achromatic color—black is the absence of color) 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).

Contents

Color

Paint

In painting, white can be created by reflecting ambient light from a white pigment. 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 specialising in the use of white in art.

There are various white pigments. Lead white, also known as flake white, is the traditional white pigment, but it is not much used now as it is toxic. Non-toxic alternatives are zinc white and titanium white. They are made from zinc oxide and titanium dioxide respectively.

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 that white was formed by combining the other colors.

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.

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.

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.

Usage, symbolism, colloquial expressions

In general, since white is opposite of black, it is often used with positive connotation. Many negative expressions with "black" have an equivalent positive expression with "white". For example, whitehat describes a person who is ethically opposed to the abuse of computer systems, in contrast with blackhat. White has also many other meanings:

  • The term white is often used in the West to denote "race" for so-called Caucasian people, i.e. people of European/West Asian descent with light skin color, whose skin color actually ranges from pink to pale brown, and overlaps with some people that might be classified as "Blacks". 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.
  • Whiteout is a weather condition in which visibility is reduced and surface definition lost in snowy environments.
  • 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 symbolic of purity (the bride has not engaged in pre-marital sex)
  • 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 (contrast position paper) industry customers. It is called white paper because it was originally bound in white.
  • 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.

See also

Web colors black silver gray white red maroon purple fuchsia green lime olive yellow orange blue navy teal aqua
                                 
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