Red

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.

On a browser that supports visual formatting in Cascading Style Sheets, the following box should appear in this color:

Lower frequencies are called infrared, or far red.

Usage, symbolism, colloquial expressions

Red that tends towards red-orange and has no hint of blue is "scarlet." Red that has no hint of yellow and leans instead towards red-violet is "crimson."

• 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.

• 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).

• 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.

• Red ink is also used to denote debt - as well as losses on a balance sheet.

• 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:
  • 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 (film) is a French film, one of trilogy by Krzysztof Kieslowski.

• Red is the color claimed by the street gangs Bloods and Norteños.

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)