In modern color theory, also known as the RGB color model, red, green and blue are additive primary colors.
Red, green and blue light combined together makes white light, and these three colors, combined in different mixtures, can produce nearly any other color.
In the Renaissance, the brilliant red costumes for the nobility and wealthy were dyed with kermes and cochineal.
The 19th century brought the introduction of the first synthetic red dyes, which replaced the traditional dyes.
The red color of blood comes from protein hemoglobin, while ripe strawberries, red apples and reddish autumn leaves are colored by anthocyanins.
Red pigment made from ochre was one of the first colors used in prehistoric art.
In the language of optics, red is the color evoked by light that stimulates neither the S or the M (short and medium wavelength) cone cells of the retina, combined with a fading stimulation of the L (long-wavelength) cone cells.
Portable, high-powered versions are also available for various applications.The intensity of each component is measured on a scale of zero to 255, which means the complete list includes 16,777,216 distinct colors and shades.The s RGB number of pure red, for example, is 255, 00, 00, which means the red component is at its maximum intensity, and there is no green or blue.Red helium–neon lasers were used commercially in Laser Disc players.The use of red laser diodes became widespread with the commercial success of modern DVD players, which use a 660 nm laser diode technology.
Modern surveys in the United States and Europe show red is also the color most commonly associated with heat, activity, passion, sexuality, anger, love and joy.