In
computing
Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes, and development of both hardware and software. Computing has scientific, e ...
, on the
X Window System
The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems.
X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting wit ...
, X11 color names are represented in a simple text file, which maps certain strings to
RGB color
The RGB color model is an additive color model in which the red, green and blue primary colors of light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three additiv ...
values. It was traditionally shipped with every
X11
The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems.
X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting wit ...
installation, hence the name, and is usually located in
''<X11root>''/lib/X11/rgb.txt
. The
web colors
Web colors are colors used in displaying web pages on the World Wide Web, and the methods for describing and specifying those colors. Colors may be specified as an RGB triplet or in hexadecimal format (a ''hex triplet'') or according to their c ...
list is descended from it but differs for certain color names.
Color names are not standardized by Xlib or the X11 protocol. The list does not show continuity either in selected
color value
Lightness is a visual perception of the luminance (L) of an object. It is often judged relative to a similarly lit object. In colorimetry and color appearance models, lightness is a prediction of how an illuminated color will appear to a stand ...
s or in
color name
A color term (or color name) is a word or phrase that refers to a specific color. The color term may refer to human perception of that color (which is affected by visual context) which is usually defined according to the Munsell color system, or t ...
s, and some color triplets have multiple names. Despite this, graphic designers and others got used to them, making it practically impossible to introduce a different list. In earlier releases of X11 (prior to the introduction of
Xcms
The X Window System core protocolRobert W. Scheifler and James Gettys: ''X Window System: Core and extension protocols, X version 11, releases 6 and 6.1'', Digital Press 1996, RFC 1013Grant EdwardsAn Introduction to X11 User Interfaces/ref> is the ...
), server implementors were encouraged to modify the RGB values in the reference color database to account for gamma correction.
As of X.Org Release 7.4 rgb.txt is no longer included in the roll up release, and the list is built directly into the server. The optional module xorg/app/rgb contains the stand-alone rgb.txt file.
The list first shipped with X10 release 3 (X10R3) on 7 June 1986, having been checked into
RCS
RCS may refer to:
Organisations
*Racing Club de Strasbourg Alsace
* Radio Corporation of Singapore
*Radcliffe Choral Society
* Rawmarsh Community School
*Red Crescent Society
*Red Cross Society
* Representation of Czechs and Slovaks, a football t ...
by
Jim Gettys
Jim Gettys (born 15 October 1953) is an American computer programmer. He was involved in multiple computer related projects.
Activity
Gettys worked at DEC's Cambridge Research Laboratory.
Until January 2009, he was the Vice President of Sof ...
in 1985. The same list was in X11R1 on 18 September 1987. Approximately the full list as is available today shipped with X11R4 on 29 January 1989, with substantial additions by Paul Ravelling (who added colors based on Sinclair Paints samples), John C. Thomas (who added colors based on a set of 72
Crayola
Crayola LLC, formerly the Binney & Smith Company, is an American manufacturing company specializing in art supplies. It is known for its brand ''Crayola'' and best known for its crayons. The company is headquartered in Forks Township, Pennsylvan ...
crayon
A crayon (or wax pastel) is a stick of pigmented wax used for writing or drawing. Wax crayons differ from pastels, in which the pigment is mixed with a dry binder such as gum arabic, and from oil pastels, where the binder is a mixture of wax an ...
s he had on hand) and Jim Fulton (who reconciled contributions to produce the X11R4 list). The project was running
DEC VT240
VT or Vt may refer to:
Businesses and organizations
* Verlag Technik, a former German publishing house
* VT F.C. (Vospers Thornycroft FC), a UK football club
* VT Group, a British defence company
* Air Tahiti (IATA airline designator VT), a Fren ...
terminals at the time, so would have worked to that device.
In some applications multipart names are written with spaces, in others joined together, often in
camel case
Camel case (sometimes stylized as camelCase or CamelCase, also known as camel caps or more formally as medial capitals) is the practice of writing phrases without spaces or punctuation. The format indicates the separation of words with a single ...
. They are usually matched insensitive of case and the X Server source code contains spaced aliases for most entries; this article uses spaces and uppercase initials except where variants with spaces are not specified in the actual code.
Clashes between web and X11 colors in the CSS color scheme
The first versions of
Mosaic
A mosaic is a pattern or image made of small regular or irregular pieces of colored stone, glass or ceramic, held in place by plaster/mortar, and covering a surface. Mosaics are often used as floor and wall decoration, and were particularly pop ...
and
Netscape Navigator
Netscape Navigator was a web browser, and the original browser of the Netscape line, from versions 1 to 4.08, and 9.x. It was the flagship product of the Netscape Communications Corp and was the dominant web browser in terms of usage share in ...
used the X11 colors as the basis for the
web colors
Web colors are colors used in displaying web pages on the World Wide Web, and the methods for describing and specifying those colors. Colors may be specified as an RGB triplet or in hexadecimal format (a ''hex triplet'') or according to their c ...
list, as both were originally X applications. The
W3C
The World Wide Web Consortium (W3C) is the main international standards organization for the World Wide Web. Founded in 1994 and led by Tim Berners-Lee, the consortium is made up of member organizations that maintain full-time staff working to ...
specifications
SVG and
CSS level 3 module Color eventually adopted the X11 list with some changes. The present W3C list is a superset of the 16 "
VGA
Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the PC industry within three years. The term can now ...
colors" defined in
HTML 3.2
The HyperText Markup Language or HTML is the standard markup language for documents designed to be displayed in a web browser. It can be assisted by technologies such as Cascading Style Sheets (CSS) and scripting languages such as JavaScript ...
and CSS level 1.
One notable difference between X11 and W3C is the case of "Gray" and its variants. In HTML, "Gray" is specifically reserved for the 128 triplet (50% gray) . However, in X11, "gray" was assigned to the 190 triplet (74.5%) , which is close to W3C "Silver" at 192 (75.3%) , and had "Light Gray" at 211 (83%) and "Dark Gray" at 169 (66%) counterparts. As a result, the combined CSS 3.0 color list that prevails on the web today produces "Dark Gray" as a significantly lighter tone than plain "Gray" , because "Dark Gray" was descended from X11 – for it did not exist in HTML nor CSS level 1 – while "Gray" was descended from HTML. Even in the current draft for CSS 4.0, dark gray continues to be a lighter shade than gray. Some browsers such as Netscape Navigator insisted on an "a" in any "Gr''a''y" except for "Light Gr''e''y".
Recent X releases also support the W3C definitions. In X11, the original definitions have been preserved (so "Dark Gray" remains a darker shade of "Gray"), but for every conflicting name pair, "Web" and additional "X11" prefixes have been added to ease disambiguation after the merger. The "X11" prefix is an alias for the non-prefixed version, i.e. "X11 Gray" = "Gray" ≠ "Web Gray". The W3C also defined a color that is equal to X11's "Green", but called it "Lime". In X11, this is simply called "Lime", as no such name existed before. It aliases to "Green", i.e. "Lime" = "Green" = "X11 Green" ≠ "Web Green".
Color name chart
The following chart presents the standardized X11 color names from the X.org source code. The
list of names accepted by browsers following
W3C standards slightly differs as explained above. The table does not show numbered gray and brightness variants as described below. Actual
rgb.txt
files and other color databases or palettes may differ since they are freely editable by vendors and users. The table shows component values in several notations of the RGB color space, i.e.
RGB
The RGB color model is an additive color model in which the red, green and blue primary colors of light are added together in various ways to reproduce a broad array of colors. The name of the model comes from the initials of the three additiv ...
,
HSL and HSV
HSL (for hue, saturation, lightness) and HSV (for hue, saturation, value; also known as HSB, for hue, saturation, brightness) are alternative representations of the RGB color model, RGB color model, designed in the 1970s by computer graphics res ...
, conversions are done assuming
sRGB
sRGB is a standard RGB (red, green, blue) color space that HP and Microsoft created cooperatively in 1996 to use on monitors, printers, and the World Wide Web. It was subsequently standardized by the International Electrotechnical Commission ( ...
color space.
* Prior to standardization as a web color, ''Gainsboro'' was included as one of the X11 color names. It was, however, absent from the original 1987 version of the list, but present in Paul Raveling's version which added, amongst other things, " ght and off-white colors, copied from several Sinclair Paints color samples".
Color variations
Shades of gray
The complete
rgb.txt
defines 101 shades from 'Gray0' (black) up to 'Gray100' (white) in addition to 'Gray' and its variants listed above. The shades are apparently defined by the formula
Gray''N'' := round(''N''% × 255)
resulting in e.g. 'Gray96' , which happens to be the same as 'White Smoke'. Similarly 'Dim Gray' is the same as 'Gray41' .
On the other hand, 'Gray' lies between 'Gray74' and 'Gray75' ; 'Dark Gray' is not the same as 'Gray66' ; and 'Light Gray' is not the same as 'Gray83' .
These shades are not included in W3C specifications, although drafts for level 4 of the CSS Color module include a similar function
gray()
.
They are still coded without 'Grey' alternatives, but with no space before the digit.
Numbered variants
For 78 colors (not counting grays),
rgb.txt
offers four variants "''color''1", "''color''2", "''color''3", and "''color''4", with "''color''1" sometimes corresponding to "''color''", so e.g. "Snow1" is the same as "Snow". Unlike base colors, e.g.
cadet blue
and
CadetBlue
, these are only coded without spaces, e.g.
CadetBlue3
. These variations are neither supported by popular browsers nor adopted by W3C standards. Whether or not a certain color has such variants seems random.
If "''color''1" is not the same as "''color'', the base color is usually darker. That means its brightness in
HSB color notation is less than 100%; about 30 of the base colors are fully bright. The four variants (1...4) have rounded brightness values of 100%, 93%, 80% and 55%, respectively. Their hue and saturation are usually the same except for rounding. In some cases they differ from the base color, though, which may indicate that these variants were specified with alternate definitions of the bases in mind, i.e. their values were adapted to a certain monitor which was commonly done by vendors until the 1990s.
The fixed brightness settings correspond closely to these formulae to determine the RGB values:
:
''color''1 := ''color'' × 100%
:
''color''2 := ''color''1 × 93.2%
:
''color''3 := ''color''1 × 80.4%
:
''color''4 := ''color''1 × 54.8%
Examples:
* "Yellow 2" (238, 238, 0) is based on "Yellow" (255, 255, 0) with 255 × 0.932 = 237.66.
* "Ivory 3" (205, 205, 193) is explained by "Ivory" (255, 255, 240) where 255 × 0.804 = 205.02 and 240 × 0.804 = 192.96.
* "Azure 4" (131, 139, 139) is close to "Azure" (240, 255, 255) values transformed as 255 × 0.548 = 139.74 and 240 × 0.548 = 131.52.
Prefixed variants
Some color names appear to be brightness or saturation modifications of others because they bear prefixes such as ''Dark, Light, Medium, Pale'' or ''Deep'', but there is no systematic variation apparent. Several sets, however, feature a ''Dark'' variant with 55% brightness and some have their ''Medium'' at about 80%.
"Light Goldenrod Yellow" and "Dark Olive Green" are special, because there are no corresponding color entries without ''Dark'' and ''Light'' prefixes.
Nuances with different hue
Several groups of colors share the same lightness or brightness and saturation. These ''nuances'' differ only by hue.
; 100%/25%: 0° (Web) Maroon, 60° Olive, 120° Green, 180° Teal, 240° Navy (Blue), 300° (Web) Purple
; 100%/27%: 0° Dark Red, 180° Dark Cyan, 240° Dark Blue, 300° Dark Magenta
; 100%/41%: 181° Dark Turquoise, 282° Dark Violet
; 100%/49%: 90° Lawn Green, 157° Medium Spring Green
; 61%/50%: 80° Yellow Green, 120° Lime Green, 280° Dark Orchid
; 100%/50%: 0° Red, 16° Orange Red, 33° Dark Orange, 39° Orange, 51° Gold, 60° Yellow, 90° Chartreuse, 120° (Lime) Green, 150° Spring Green, 180° Aqua / Cyan, 195° Deep Sky Blue, 240° Blue, 300° Fuchsia / Magenta
; 25%/65%: 0° Rosy Brown, 120° Dark Sea Green
; 59–60%/65%: 260° Medium Purple, 302° Orchid, 340° Pale Violet Red
; 100%/86%: 38° Moccasin, 351° Light Pink
; 100%/90%: 36° Blanched Almond, 54° Lemon Chiffon
; 67%/94%: 30° Linen, 240° Lavender
; 100%/94%: 6° Misty Rose, 60° Light Yellow, 180° Light Cyan
; 100%/97%: 25° Seashell, 40° Floral White, 60° Ivory, 120° Honeydew, 180° Azure, 208° Alice Blue, 340° Lavender Blush
; 100%/99%: 0° Snow, 240° Ghost White
Tints and shades with different lightness
Several groups of colors share the same hue and HSL saturation. ''Tints'' are lighter than a base color,
''shades'' are darker.
; 0°/0%: 0% Black, 41% Dim Gray, 50% (Web) Gray, 66% Dark Gray, 75% (X11) Gray, 75% Silver, 83% Light Gray, 86% Gainsboro, 96% White Smoke, 100% White
; 0°/100%: 25% (Web) Maroon, 27% Dark Red, 50% Red, 99% Snow
; 16°/100%: 50% Orange Red, 66% Coral
; 33°/100%: 50% Dark Orange, 88% Bisque
; 36°/100%: 84% Navajo White, 90% Blanched Almond
; 60°/100%: 25% Olive, 50% Yellow, 94% Light Yellow, 97% Ivory
; 80°/61%: 35% Olive Drab, 50% Yellow Green
; 90°/100%: 49% Lawn Green, 50% Chartreuse
; 120°/61%: 34% Forest Green, 50% Lime Green
; 120°/100%: 20% Dark Green, 25% (Web) Green, 50% (X11) Green / Lime, 97% Honeydew
; 146–147°/50%: 36% Sea Green, 47% Medium Sea Green
; 150°/100%: 50% Spring Green, 98% Mint Cream
; 180–181°/100%: 25% Teal, 27% Dark Cyan, 41% Dark Turquoise, 50% Aqua / Cyan, 94% Light Cyan, 97% Azure
; 240°/100%: 25% Navy Blue, 27% Dark Blue, 40% Medium Blue, 50% Blue, 99% Ghost White
; 300°/100%: 25% (Web) Purple, 27% Dark Magenta, 50% Fuchsia / Magenta
; 328–330°/100%: 54% Deep Pink, 71% Hot Pink
; 350–351°/100%: 88% Pink, 86% Light Pink
Tones with different saturation
Some pairs of colors share the same lightness and hue. These ''tones'' differ only by saturation. Tones are far less common in the X11 set than nuances, tints and shades.
; 0°/41%: 0% Dim Gray, 59% Brown
; 120°/50%: 61% Lime Green, 100% Green / Lime
; 180°/25%: 25% Dark Slate Gray, 100% Teal
; 240°/27%: 64% Midnight Blue, 100% Dark Blue
Derived lists
The Printer Working Group (PWG) of the
IEEE
The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operation ...
publishes a standard
PWG 5101.1 whose mandatory color names are based upo
RFC 3805 successor t
RFC 1759which imported the functional color names ''other'', ''unknown'' and ''transparent'' alongside seven basic colors from
ISO 10175
ISO is the most common abbreviation for the International Organization for Standardization.
ISO or Iso may also refer to: Business and finance
* Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007
* Iso ...
(
DPA) and
ISO 10180
ISO is the most common abbreviation for the International Organization for Standardization.
ISO or Iso may also refer to: Business and finance
* Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007
* Iso ...
(
SPDL), and JTAPI.
This standard has four variants for each non-monochromatic color: ''clear'' (50% transparent), ''dark'', ''light'' and the default. Wherever possible, the values are the same as in the W3C adaptation of the X11 list, except for Turquoise which is instead of . Missing variant values have been added systematically. ''Buff'' and ''Mustard'' are completely new color names. Light Black and Gray correspond to the same color.
See also
*
List of colors
These are the lists of colors;
* List of colors: A–F
* List of colors: G–M
* List of colors: N–Z
* List of colors (compact)
* List of colors by shade
* List of color palettes
* List of Crayola crayon colors
* List of RAL colors
* List ...
*
XPM (image format)
X PixMap (XPM) is an image file format used by the X Window System, created in 1989 by Daniel Dardailler and Colas Nahaboo working at Bull Research Center at Sophia Antipolis, France, and later enhanced by Arnaud Le Hors.
It is intended primaril ...
*
Web colors § X11 color names
References
External links
X-Server source code with built-in colors"Extended Color Keywords", ''CSS Color Module Level 3'' a W3C Recommendation
X11 rgb.txt 1.1at Xfree.86.org, 1994, and
X11 rgb.txt 1.2 2005 (excluding 96 aliases).
* Aubrey Jaffer
"Color-Name Dictionaries" Jaffer's page includes extensive information about and comparisons between color-name dictionaries.
{{Color shades
Color names
X Window System
Cascading Style Sheets