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White
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).
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.
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.
A Whitehat, also rendered as White hat or White-hat, is, in the realm
of Information technology, a name that describes a person who is ethically
opposed to the abuse of Computer systems.
Usage, symbolism, colloquial expressions
1. 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".
2. White noise, in acoustics, is a sibilant sound that is often a nuisance,
although it can also be deliberately created for test purposes.
3. Whitewash, figuratively, means an attempt to obscure the truth by issuing
a blanket of lies.
4. Whiteout is a weather condition in which visibility is reduced and
surface definition lost in snowy environments.
5. In Chinese and Indian tradition, white is the color of mourning, death,
and ghosts.
6. In English heraldry, white or silver (color) signified brightness,
purity, virtue, and innocence. (The American Girls Handy Book, p.369)
7. 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)
8. White is often associated with Conservatism (as opposed to Communism),
particularly in the years following World War I, with civil wars fought
between "Reds" and "Whites", for instance the Civil
War in Russia and the Civil War in Finland.
9. A white flag is an international sign of either surrender, or truce,
that is, it is a sign of peaceful intent, typically at time of war.
10. 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.
11. The white ribbon is worn by movements denouncing violence against
women and against queer youth. It is also worn by some feminists and was
a symbol for peace in Quebec, in the beginning of 2003, as part of the
popular opposition to war on Iraq.
12. 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.
13. White is also one of the two opponents in many board games of abstract
strategy, such as go, chess, and checkers.
14. In both the French and Russian Revolutions, white symbolized royalism.
Arthur Charles Fox-Davies has argued that white can be considered a tincture
in heraldry separate from its use to represent argent, and in fact the
labels borne on the arms, crests and supporters of members of the British
Royal Family other than the reigning sovereign are invariably shown as
white. The color is also used extensively by the Roman Catholic pope.
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