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The following is a partial list of colors with associated articles. See also color names and the list of color topics.

Note that a large percentage of the color swatches below are taken from computer-domain-specific naming schemes such as X11 or HTML4 (see also web colors). RGB values are given for each swatch, because such standards are defined in terms of the sRGB color space. It is not possible to accurately convert many of these swatches to CMYK values, because of the differing gamuts of the two spaces. But color management systems built in to operating systems and image editing software can attempt such conversions as accurately as possible.

The HSV (Hue, Saturation, Value) values, also known as HSB (Hue, Saturation, Brightness), and Hex Triplets (for HTML Web colors) are also given in the following table. Colors which appear on the Web-safe color palette?which includes the sixteen named colors?are noted. (Those four named colors corresponding to the neutral grays can be rendered with any Hue value, which is effectively ignored.)

The appearance of actual color swatches displayed below will vary depending on many parameters, such as the properties of the display device, color management settings, and the viewing surround conditions.

Note also that color naming is fuzzy and arbitrary, and varies between people and cultures; no single swatch is adequately representative of any particular color name. Additionally, computer displays have somewhat limited gamut, so many colorful pigments cannot be represented on screen at all, and computer simulation of the natural world is at best a rough approximation.

In the arts of painting, graphic design, color printing, television, web design, and photography, color theory or colour theory (UK spelling) is a body of practical guidance to color mixing and the visual impact of specific color combinations. Although color theory principles first appear in the writings of Leone Battista Alberti (c.1435) and the notebooks of Leonardo da Vinci (c.1490), a tradition of "colory theory" begins in the 18th century, initially within a partisan controversy around Isaac Newton's theory of color (Opticks, 1704) and the nature of so-called primary colors. From there it developed as an independent artistic tradition with only superficial reference to colorimetry and vision science.

Color or colourSee American and British English spelling differences. is the visual perceptual property corresponding in humans to the categories called red, yellow, blue, black, etc. Color derives from the spectrum of light (distribution of light energy versus wavelength) interacting in the eye with the spectral sensitivities of the light receptors. Color categories and physical specifications of color are also associated with objects, materials, light sources, etc., based on their physical properties such as light absorption, reflection, or emission spectra.

Typically, only features of the composition of light that are detectable by humans (wavelength spectrum from 400 nm to 700 nm, roughly) are included, thereby objectively relating the psychological phenomenon of color to its physical specification.

Because perception of color stems from the varying sensitivity of different types of cone cells in the retina to different parts of the spectrum, colors may be defined and quantified by the degree to which they stimulate these cells. These physical or physiological quantifications of color, however, do not fully explain the psychophysical perception of color appearance.

The science of color is sometimes called chromatics. It includes the perception of color by the human eye and brain, the origin of color in materials, color theory in art, and the physics of electromagnetic radiation in the visible range (that is, what we commonly refer to simply as Light).

Theory of Colours (original German title, Zur Farbenlehre) is a book by Johann Wolfgang von Goethe published in 1810. The work comprises three sections: i) a didactic section in which Goethe presents his own observations, ii) a polemic section in which he makes his case against Newton, and iii) an historical section. It contains some of the earliest and most accurate descriptions of phenomena such as coloured shadows, refraction, and chromatic aberration.

Its influence extends primarily to the art world, especially among the Pre-Raphaelites. J. M. W. Turner studied it comprehensively, and referenced it in the titles of several paintings (Bockemuhl, 1991). Wassily Kandinsky considered Goethe's theory, "one of the most important works." .

Although Goethe's work was never well received by physicists, a number of philosophers and physicists have been known to have concerned themselves with it, including Arthur Schopenhauer, Kurt Gödel, Werner Heisenberg, Ludwig Wittgenstein, and Hermann von Helmholtz. Mitchell Feigenbaum had even convinced himself that 'Goethe had been right about colour!' (Ribe & Steinle, 2002 ).

In his book, Goethe provides a general exposition of how colour is perceived in a variety of circumstances, and considers Isaac Newton's observations to be special casesPhysics Today July 2002. Goethe's concern was not so much with the analytic measurement of colour phenomenon, as with the qualities of how phenomena are perceived. Science has come to understand the distinction between the optical spectrum, as observed by Newton, and the phenomenon of human colour perception as presented by Goethe.

In colorimetry and color theory, colorfulness, chroma, and saturation are related concepts referring to the intensity of a specific color. Though this general concept is intuitive, terms such as chroma, saturation, purity, and intensity are often used without great precision, and even when well-defined depend greatly on the specific color model in use. More technically,

; colorfulness : is the perceived difference between the color of some stimulus and gray,

; chroma : is the colorfulness of a stimulus relative to the brightness of a stimulus that appears white under similar viewing conditions,

; saturation : is the colorfulness of a stimulus relative to its own brightness.Mark D. Fairchild. ?Color Appearance Models: CIECAM02 and Beyond?. Slides from a tutorial at the IS&T/SID 12th Color Imaging Conference. 9 November 2004. Retrieved 19 September 2007.

A highly colorful stimulus is vivid and intense, while a less colorful stimulus appears more muted, closer to gray. With no colorfulness at all, a color is a ?neutral? gray. With three attributes?colorfulness (or chroma or saturation), lightness (or brightness), and hue?any color can be described.

Image:Surfing in Hawaii.jpg|Original image

Image:Surfing in Hawaii (retouched).jpg|Contrast and saturation increased

are cyclically rotated with time.]]

Hue is one of the three main attributes of perceived color, in addition to lightness and chroma (or colorfulness). Hue is also one of the three dimensions in some colorspaces along with saturation, and brightness (also known as lightness or value). Hue is that aspect of a color described with names such as "red", "yellow", etc.

Usually, colors with the same hue are distinguished with adjectives referring to their lightness and/or chroma, such as with "light blue", "pastel blue", "vivid blue". Notable exceptions include brown, which is a dark orange,C J Bartleson, "Brown". Color Research and Application, 1 : 4, p 181-191 (1976). and pink, a light red with reduced chroma.

In painting color theory, a hue refers to a pure color?one without tint or shade (added white or black pigment, respectively). A hue is an element of the color wheel.

Complementary colors are pairs of colors that are of ?opposite? hue in some color model. The exact hue ?complementary? to a given hue depends on the model in question, and perceptually uniform, additive, and subtractive color models, for example, have differing complements for any given color.

An additive color model involves light emitted directly from a source or illuminant of some sort. The additive reproduction process usually uses red, green and blue light to produce the other colors. See also RGB color model. Combining one of these additive primary colors with another in equal amounts produces the additive secondary colors cyan, magenta, and yellow. Combining all three primary lights (colors) in equal intensities produces white. Varying the luminosity of each light (color) eventually reveals the full gamut of those three lights (colors). Computer monitors and televisions are the most common application of additive color.

Results obtained when mixing additive colors are often counterintuitive for people accustomed to the more everyday subtractive color system of pigments, dyes, inks and other substances which present color to the eye by reflection rather than emission. For example, in subtractive color systems green is a combination of yellow and blue, in additive color, red + green = yellow and no simple combination will yield green. It should be noted that additive color is a result of the way the eye detects color, and is not a property of light. There is a vast difference between yellow light, with a wavelength of approximately 580 nm, and a mixture of red and green light. However, both stimulate our eyes in a similar manner, so we do not detect that difference. (see eye (cytology), color vision.)

James Clerk Maxwell is credited as being the father of additive color. He had the photographer Thomas Sutton photograph a tartan ribbon three times, first with a red, then green, then blue color filter over the lens. The three images were developed and then projected onto a screen with three different projectors, each equipped with the corresponding red, green, or blue color filter used to take its image. When brought into register, the three images formed a full color image, thus demonstrating the principles of additive color.

HSL and HSV are two related representations of points in an RGB color space, which attempt to describe perceptual color relationships more accurately than RGB, while remaining computationally simple. HSL stands for hue, saturation, lightness, while HSV stands for hue, saturation, value.

HSI and HSB are alternative names for these concepts, using intensity and brightness; their definitions are less standardized, but they are typically interpreted as synonymous with HSL.

Both HSL and HSV describe colors as points in a cylinder whose central axis ranges from black at the bottom to white at the top with neutral colors between them, where angle around the axis corresponds to ?hue?, distance from the axis corresponds to ?saturation?, and distance along the axis corresponds to ?lightness?, ?value?, or ?brightness?.

The two representations are similar in purpose, but differ somewhat in approach. Both are mathematically cylindrical, but while HSV (hue, saturation, value) can be thought of conceptually as an inverted cone of colors (with a black point at the bottom, and fully-saturated colors around a circle at the top), HSL conceptually represents a double-cone or sphere (with white at the top, black at the bottom, and the fully-saturated colors around the edge of a horizontal cross-section with middle gray at its center). Note that while ?hue? in HSL and HSV refers to the same attribute, their definitions of ?saturation? differ dramatically.

Because HSL and HSV are simple transformations of device-dependent RGB, the color defined by a (h, s, l) or (h, s, v) triplet depends on the particular color of red, green, and blue ?primaries? used. Each unique RGB device therefore has unique HSL and HSV spaces to accompany it. An (h, s, l) or (h, s, v) triplet can however become definite when it is tied to a particular RGB color space, such as sRGB.

Both models were first formally described in 1978 by Alvy Ray Smith, though the concept of describing colors by these three dimensions, or equivalents such as hue, chroma, and tint, was introduced much earlier.

In colorimetry, the Munsell color system is a color space that specifies colors based on three color dimensions, hue, value (lightness), and chroma (color purity or colorfulness). It was created by Professor Albert H. Munsell in the first decade of the 20th century.

Several earlier color order systems had placed colors into a three dimensional color solid of one form or another, but Munsell was the first to separate hue, value, and chroma into perceptually uniform and independent dimensions, and was the first to systematically illustrate the colors in three dimensional space.Kuehni (2002), p 21 Munsell's system, and particularly the later renotations, is based on rigorous measurements of human subjects' visual responses to color, putting it on a firm experimental scientific basis. Because of this basis in human visual perception, Munsell's system has outlasted its contemporary color models, and though it has been superseded for some uses by models such as CIELAB (L*a*b*) and CIECAM02, it is still in wide use today. Landa (2005), pp 437?438,

CMYK (short for cyan, magenta, yellow, and key (black),The ?K? in CMYK stands for key, as in four-color printing, cyan, magenta, and yellow printing plates are carefully keyed or aligned with the key line of the black key plate. Some sources suggest that the ?K? in CMYK comes from the last letter in ?black?, for instance Mark Galer and Les Horvat (2002). Digital Imaging: Essential Skills. Focal Press. and Simon Jennings (2003). Artists Color Manual: The Complete Guide to Working with Color. Chronicle Books. However, such explanations are likely inaccurate, plausible inventions of authors unfamiliar with traditional printing technology. Mark Gatter (2005). Getting It Right in Print: Digital Pre-press for Graphic Designers. Laurence King Publishing. and often referred to as process color or four color) is a subtractive color model, used in color printing, also used to describe the printing process itself. Though it varies by print house, press operator, press manufacturer and press run, ink is typically applied in the order of the abbreviation.Press Operator (interview) October 27, 2006. Dynagraphics.

The CMYK model works by partially or entirely masking certain colors on the typically white background (that is, absorbing particular wavelengths of light). Such a model is called subtractive'' because inks ?subtract? brightness from white.

In additive color models such as RGB, white is the ?additive? combination of all primary colored lights, while black is the absence of light. In the CMYK model, it is just the opposite: white is the natural color of the paper or other background, while black results from a full combination of colored inks. To save money on ink, and to produce deeper black tones, unsaturated and dark colors are produced by substituting black ink for the combination of cyan, magenta and yellow.

x,y chromaticity space, also showing the chromaticities of black-body light sources of various temperatures (Planckian locus), and lines of constant correlated color temperature.]]

Color temperature is a characteristic of visible light that has important applications in photography, videography, publishing and other fields. The color temperature of a light source is determined by comparing its chromaticity with a theoretical, heated black-body radiator. The temperature (usually measured in kelvin (K)) at which the heated black-body radiator matches the color of the light source is that source's color temperature; for a black body source, it is directly related to Planck's law.