Red

#FF0000

Red is a color at the lowest frequencies of light discernible by the human eye. Red light has a wavelength of roughly 700 nm. Oxygenated blood is red due to the presence of hemoglobin. Red light is the first to be absorbed by sea water, so that many fish and marine invertebrates that appear bright red, are black in their native habitat.

Red is an additive primary colour, complementary to cyan. It was once considered to be a subtractive primary colour, and is still sometimes described as such in non-scientific literature; however, the colours cyan, magenta and yellow are now known to be closer to the true primary colours detected by the eye, and are used in modern colour printing. But in the RGB color model used on TV sets and computer monitors, red is one of the three channels, designated R.

Lower frequencies are called infrared, or far red.

A red filter used in black and white photography increases contrast in most scenes. For example, combined with a polarizer, it can turn the sky black. Films simulating the effects of infrared film (such as Ilford's SFX 200) do so by being much more sensitive to red than to other colors.

Contents

1 Usage, symbolism, colloquial expressions

2 Color coordinates

3 Variations

4 See also

Usage, symbolism, colloquial expressions

Red catches people's attention, and is often seen as a sign of danger: it is thus used for warning signs.
- The color red is often used to denote anger as in seeing red.
- The color of blood led red to be associated with the god of war, Mars, and the reddish planet Mars became named for him.
- Red is used to denote "stop" in traffic signs and traffic signals.
- In auto racing, a red flag signals all cars to immediately stop.
Red is the color of love, both in the red hearts of a valentine, and in a "red-light district".
Red is one of the Christmas colors.
Beginning with the Revolution of 1848, "Socialist" red was used as a color of European Revolutionaries, like Garibaldi's camicie rosse ("redshirts") in the Italian Risorgimento, and taken up by Leftist and generally radical groups, while the white of legitimist Borbon partisans became associated with pre-World War I conservatives.
- For instance the Civil War in Russia and the Civil War in Finland were fought between "Reds" and "Whites".
- The identification of Communism with "Socialist" red (and with red being the primary color of the flag of the Soviet Union) led to such Cold War phrases as "the Red Menace" and "Red China" (distinguished from Nationalist China, "Free China," or Taiwan).

Chinese wedding gown

In Chinese symbolism, red is the color of good luck and is used for decoration and wedding attire. Money in Chinese societies is traditionally given in red packets. See also The East is Red. Mao Zedong was sometimes referred to as a "red sun".
Red ink is also used to denote debt - as well as losses on a balance sheet (hence the phrase, "in the red" usually indicates economic losses).
In North American stock markets, red is used to denote a drop in stock prices. In East Asian stock markets, red is used to denote a rise in stock prices.
In maps of political parties, red is traditionally used for the following parties:
- Australia: Labor
- Canada: Liberal Party of Canada
- Germany: Sozialdemokratische Partei Deutschlands (Social Democratic party of Germany) and Partei des Demokratischen Sozialismus (Party of Democratic Socialism)
- The Netherlands: Partij van de Arbeid (Socialist party)
- United Kingdom: Labour Party
- United States: Republican Party
In the history of Japan red is the color of military flags used by the Heike (or Taira) clan and of the Genji (or Minamoto) clan, two clans that struggled for power at the close of the Heian era, in the late 12th century.
Red is the last film in the Three Colors trilogy by Krzysztof Kieślowski.
Red is the color claimed by the street gangs Bloods and Norteños.
Red is the word for the fish Myripristis Sp. in Tobian
Red is an album by progressive rock band King Crimson.

Color coordinates

Hex triplet = #FF0000
RGB    (r, g, b)    =  (255, 0, 0)
CMYK   (c, m, y, k) =  (0, 255, 255, 0)
HSV    (h, s, v)    =  (0, 100, 100)

Variations

Scarlet - a shade of red that tends towards red-orange and has no hint of blue
Vermilion - a fiery shade of red that tends toward red-orange to a silghtly greater degree than scarlet, prepared from cinnabar, the artificial red sulphide of mercury used as a pigment
Crimson - a shade of red that has no hint of yellow and leans towards red-violet
Venetian Red (also known as India Red and Indian Red) - A shade of brownish red prepared from sulphate of iron.
Fire Engine Red - A shade of bright red commonly used on emergency vehicles
"Jungle Red" was the nailpolish color in The Women.

Electromagnetic Spectrum