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Web colors are colors used in designing web pages, and the methods for describing and specifying those colors. HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure HTML has been in use since 1991, but HTML 40 (December 1997 was the first standardized version where international characters were given reasonably complete treatment Dynamic HTML, or DHTML, is a collection of technologies used together to create interactive and animated Web sites by using a combination of a static Markup In HTML and XHTML, a font face or font family is the typeface that is applied to some text An HTML editor is a software application for creating Web pages Although the HTML markup of a web page can be written with any Text editor, specialized In Computing, an HTML element indicates structure in an HTML document and a way of hierarchically arranging content HTML Series The W3C HTML standard includes support for Client-side scripting. A layout engine, or rendering engine, is software that takes marked up content (such as HTML, XML, image files etc Quirks mode refers to a technique used by some Web browsers for the sake of maintaining backwards compatibility with Web pages designed for older browsers instead of Web style sheets are a form of Separation of presentation and content for Web design in which the markup (i Web pages authored using hypertext markup language ( HTML) may contain multilingual text represented with the Unicode universal character set. The Extensible Hypertext Markup Language, or XHTML, is a The following tables compare general and technical information for a number of Web browsers Please see the individual products' articles for further information The following tables compare HTML compatibility and support for a number of Layout engines Please see the individual products' articles for further information The following tables compare support of HTML 5 differences from HTML 4 for a number of Layout engines The specification is still a working draft not The following tables compare deprecated and proprietary HTML tags and attributes compatibility and support for a number of Layout engines Please see the individual products' articles for The following tables compare XHTML compatibility and support for a number of Layout engines Please see the individual products' articles for further information The World Wide Web (commonly shortened to the Web) is a system of interlinked Hypertext documents accessed via the Internet.
Authors of web pages have a variety of options available for specifying colors for elements of web documents. Colors may be specified as an RGB triplet in hexadecimal format (a hex triplet); they may also be specified according to their common English names in some cases. In Mathematics and Computer science, hexadecimal (also base -, hexa, or hex) is a Numeral system with a English is a West Germanic language originating in England and is the First language for most people in the United Kingdom, the United States Often a color tool or other graphics software is used to generate color values. A Color tool is an application usually found within Graphics software and online used for the purposes of Color management, creating Color schemes picking In Computer graphics, graphics software or image editing software is a program or collection of programs that enable a person to manipulate visual images
The first versions of Mosaic and Netscape Navigator used the X11 color names as the basis for their color lists, as both started as X Window System applications. Mosaic is the browser which popularized the World Wide Web. It was also a browser for earlier concepts such as Ftp, Usenet, and Gopher Netscape Navigator and Netscape are the names for the proprietary Web browser popular in the 1990s and the Flagship product of the Netscape In Computing, on the X Window System, X11 color names are represented in a simple text file which maps certain strings to RGB Color values
Web colors have an unambiguous colorimetric definition, sRGB, which relates the chromaticities of a particular phosphor set, a given transfer curve, adaptive whitepoint, and viewing conditions. sRGB is a standard RGB (Red Green Blue color space created cooperatively by HP and Microsoft for use on monitors printers and the Internet Chromaticity is an objective specification of the Quality of a Color regardless of its luminance that is as determined by its Colorfulness (or saturation A phosphor is a substance that exhibits the phenomenon of Phosphorescence (sustained glowing after exposure to energized particles such as Electrons These have been chosen to be similar to many real-world monitors and viewing conditions, so that even without color management rendering is fairly close to the specified values. In digital imaging systems color management is the controlled conversion between the Color representations of various devices such as Image scanners Digital However, user agents vary in the fidelity with which they represent the specified colors. A user agent is the client application used with a particular Network protocol; the phrase is most commonly used in reference to those which access the World More advanced user agents use color management to provide better color fidelity; this is particularly important for Web-to-print applications.
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Hex triplet
A hex triplet is a six-digit, three-byte hexadecimal number used in HTML, CSS, SVG, and other computing applications, to represent colors. A byte (pronounced "bite" baɪt is the basic unit of measurement of information storage in Computer science. In Mathematics and Computer science, hexadecimal (also base -, hexa, or hex) is a Numeral system with a HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure The bytes represent the red, green and blue components of the color. One byte represents a number in the range 00 to FF (in hexadecimal notation), or 0 to 255 in decimal notation. This represents the least (0) to the most (255) intensity of each of the color components. The hex triplet is formed by concatenating three bytes in hexadecimal notation, in the following order:
- Byte 1: red value (color type red)
- Byte 2: green value (color type green)
- Byte 3: blue value (color type blue)
For example, consider the color where the red/green/blue values are decimal numbers: red=36, green=104, blue=160 (a greyish-blue color). The decimal numbers 36, 104 and 160 are equivalent to the hexadecimal numbers 24, 68 and A0 respectively. To obtain the hex triplet, we simply write the three hex bytes together without spaces, thus: 2468A0.
Note that if any one of the three color values is less than 16 (decimal) or 10 (hex), it must be represented with a leading zero so that the triplet always has exactly six digits. For example, the decimal triplet 4, 8, 16 would be represented by the hex digits 04, 08, 10, forming the hex triplet 040810.
The number of colors that can be represented by this system is
An abbreviated, three (hexadecimal) digit form is sometimes used. [1] Expanding this form to the six-digit form is as simple as doubling each digit: 09C becomes 0099CC. This allows each color value to cover its full range from 00 to FF.
Converting RGB to hexadecimal
Converting a decimal RGB value to a hexadecimal value is fairly straightforward. Decimal RGB values are usually given in the 0-255 range; if they are in the 0-1 range, multiply the value by 255 before conversion. This number divided by 16 (integer division; ignoring any remainder) gives us the first hexadecimal digit (between 0 and F, where the letters A to F represent the numbers 10 to 15. See hexadecimal for more details). In Mathematics and Computer science, hexadecimal (also base -, hexa, or hex) is a Numeral system with a The remainder gives us the second hexadecimal digit. For instance the RGB value 201 divides into 12 groups of 16, thus the first digit is C. A remainder of 9 gives us the hexadecimal number C9. This process is repeated for each of the three color values. Most modern operating systems have a built-in calculator to perform conversions between number bases and this can also be done with some hand-held calculators. An operating system (commonly abbreviated OS and O/S) is the software component of a Computer system that is responsible for the management and coordination This task can also be carried out using various web resources. [2]
HTML color names
The HTML 4. See also Web colors The HTML 401 specification defines sixteen named colors as follows (names are defined in this context to be case-insensitive the table is alphabetically HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure 01 specification[3] defines sixteen named colors, as follows (names are defined in this context to be case independent; the table is alphabetically ordered):
| Color | Hexadecimal | Color | Hexadecimal | Color | Hexadecimal | Color | Hexadecimal |
|---|---|---|---|---|---|---|---|
| aqua | #00FFFF | green | #008000 | navy | #000080 | silver | #C0C0C0 |
| black | #000000 | grey | #808080 | olive | #808000 | teal | #008080 |
| blue | #0000FF | lime | #00FF00 | purple | #800080 | white | #FFFFFF |
| fuchsia | #FF00FF | maroon | #800000 | red | #FF0000 | yellow | #FFFF00 |
These 16 were also specified as sRGB and included in the HTML 3. Aqua is a Cyan color used mostly by Graphic designers and other Computer -related professionals such as Web designers Aqua is identical Green is a Color, the perception of which is evoked by light having a spectrum dominated by energy with a Wavelength of roughly 520–570- nm. Navy blue is a dark shade of the Color Blue. Navy blue got its name from the dark blue (contrasted with white worn by officers in the Royal Navy since Silver is the metallic shade resembling Gray, closest to that of polished Silver. Black is the Color of objects that do not emit or Reflect Light in any part of the Visible spectrum; they absorb all such frequencies of See also Green This article is about notable Tints and shades of the Color Green. Teal, also called teal blue, is a medium to dark Blueish Green Color of low saturation; a dark Cyan. Blue is a Colour, the Perception of which is evoked by Lime green is a Color between Yellow and Green, so named because it is a representation of the color of the citrus fruit called limes Purple is a general term for the range of shades of Color occurring between Red and Blue. White is a Color, the perception which is evoked by Light that stimulates all three types of color sensitive Cone cells in the Human eye Fuchsia is a Color named after the Flower of the Fuchsia plant Maroon is a dark Brownish Red Color. The first recorded use of Maroon as a color name in English was in 1789. Red is any of a number of similar Colors evoked by light consisting predominantly of the longest wavelengths of Light discernible by the human eye in the wavelength Yellow is the Color evoked by light that stimulates both the L and M (long and medium wavelength Cone cells of the Retina about equally 0 specification which noted "These colors were originally picked as being the standard 16 colors supported with the Windows VGA palette. The term Video Graphics Array ( VGA) refers specifically to the display hardware first introduced with the IBM PS/2 line of computers in 1987, but through its widespread " [4]
X11 color names
In addition, a number of colors are defined by web browsers. A web browser is a software application which enables a user to display and interact with text images videos music games and other information typically located on a A particular browser may not recognize all of these colors, but as of 2005 all modern general-use browsers support the full list. Year 2005 ( MMV) was a Common year starting on Saturday (link displays full calendar of the Gregorian calendar. Many of these colors are from the list of X11 color names distributed with the X Window System. In Computing, on the X Window System, X11 color names are represented in a simple text file which maps certain strings to RGB Color values These colors were standardized by SVG 1.0, and are accepted by SVG Full user agents. They are not part of SVG Tiny.
Almost the exact same color names are used in .NET Framework, in the KnownColor and Color enumerations. The only color difference is DarkSeaGreen which is defined as 8F,BC,8B (instead of 8F,BC,8F).
The list of colors actually shipped with the X11 product varies between implementations, and clashes with certain of the HTML names such as green. Furthermore, X11 colors are defined as simple RGB (hence, no particular color), rather than sRGB. This means that the list of colors found in X11 (e. g. in /usr/lib/X11/rgb. txt) should not directly be used to choose colors for the web. [5]
The list of web "X11 colors" from the CSS3 specification, along with their hexadecimal and decimal equivalents, is shown below, compare the alphabetical lists in the W3C standards. [6] [7]
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Web-safe colors
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1-bit monochrome 8-bit color |
| Related |
Another set of 216 color values is commonly considered to be the "web-safe" color palette, developed at a time when many computer displays were only capable of displaying 256 colors. HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure In Mathematics and Computer science, hexadecimal (also base -, hexa, or hex) is a Numeral system with a In Communications a code is a rule for converting a piece of Information (for example a letter, Word, Phrase, or In Communications a code is a rule for converting a piece of Information (for example a letter, Word, Phrase, or HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure In Mathematics and Computer science, hexadecimal (also base -, hexa, or hex) is a Numeral system with a In Communications a code is a rule for converting a piece of Information (for example a letter, Word, Phrase, or In Communications a code is a rule for converting a piece of Information (for example a letter, Word, Phrase, or HTML, an initialism of HyperText Markup Language, is the predominant Markup language for Web pages It provides a means to describe the structure In Mathematics and Computer science, hexadecimal (also base -, hexa, or hex) is a Numeral system with a In Communications a code is a rule for converting a piece of Information (for example a letter, Word, Phrase, or In Communications a code is a rule for converting a piece of Information (for example a letter, Word, Phrase, or Color depth. or bit depth, is a Computer graphics term describing the number of Bits used to represent the Color of a single Pixel A binary image is a Digital image that has only two possible values for each Pixel. In Computing, a grayscale or greyscale Digital image is an image in which the value of each Pixel 8-bit color graphics is a method of storing image information in a computer's memory or in an image file such that each Pixel is represented by one 8-bit Byte. Highcolor graphics (variously spelled Hicolor, Hicolour, and Highcolour, and known as Thousands of colors on a Macintosh) is a method See also True Colors (disambiguation. Truecolor is a method of representing and storing graphical image information (especially in computer Deep Color is a term used to describe a method of representing graphical image data using an extremely large number of shades hues and luminosities capable of displaying billions of possible In computing indexed color is a technique to manage Digital images colors in a limited fashion in order to save computer's memory and file storage In Computer graphics, a palette is either a given finite set of Colors for the management of Digital images (that is a color palette) or Web colors are Colors used in designing web pages and the methods for describing and specifying those colors A set of colors was needed that could be shown without dithering on 256-color displays; the number 216 was chosen partly because computer operating systems customarily reserved sixteen to twenty colors for their own use; it was also selected because it allows exactly six shades each of red, green, and blue (6 × 6 × 6 = 216). Dither is an intentionally applied form of Noise, used to randomize Quantization error, thereby preventing large-scale patterns such as contouring that are more objectionable
The list of colors is often presented as if it has special properties that render them immune to dithering. In fact, on 256-color displays applications can set a palette of any selection of colors that they choose, dithering the rest. These colors were chosen specifically because they matched the palettes selected by the then leading browser applications. Fortunately, there were not radically different palettes in use in different popular browsers.
"Web-safe" colors had a flaw in that, on systems such as X11 where the palette is shared between applications, smaller color cubes (5x5x5 or 4x4x4) were often allocated by browsers — thus, the "web safe" colors would actually dither on such systems. Better results were obtained by providing an image with a larger range of colors and allowing the browser to quantize the color space if needed, rather than suffer the quality loss of a double quantization. Algorithms Most standard techniques treat color quantization as a problem of clustering points in three-dimensional space where the points represent colors found in the original
As of 2007, personal computers typically have at least 16-bit color and usually 24-bit (TrueColor). See also True Colors (disambiguation. Truecolor is a method of representing and storing graphical image information (especially in computer Even mobile devices have at least 16-bit color, driven by the inclusion of cameras on cellphones. The use of "web-safe" colors has fallen into practical disuse, but persisted in culture.
The web-safe palette system persists as being the palette with the greatest number of distinct colors, where each color can be distinguished individually by human eyes. This led to the use of web-safe colors in anti-phishing systems. In the field of computer security phishing is the Criminally Fraudulent process of attempting to acquire sensitive information such as usernames Passwords [8]
The "web-safe" colors do not all have names, but each can be specified by an RGB triplet. Below are the values for the 6 shades of each color out of 256 possible color shades.
| digit | hexadecimal | decimal |
|---|---|---|
| 0 | 00 | 0 |
| 3 | 33 | 51 |
| 6 | 66 | 102 |
| 9 | 99 | 153 |
| C or (12) | CC | 204 |
| F or (15) | FF | 255 |
The following table shows all of the "web-safe" colors, underlining the really-safe colors. The lack of gamma correction means that the six desired intensities 0%, 20%, 40%, 60%, 80%, and 100% are displayed as 0%, 2%, 10%, 28%, 57%, and 100% on a Windows standard 2. Gamma correction, gamma nonlinearity, gamma encoding, or often simply gamma, is the name of a nonlinear operation used to code and decode luminance Microsoft Windows is a series of Software Operating systems and Graphical user interfaces produced by Microsoft. 5 gamma CRT or LCD, making most colors very dark. The intensities at the low end of the range, especially 0 and 3, are nearly indistinguishable from each other:
Color table
Note that in the table below, each color code listed is a short-hand for the RGB value; for example, code 609 is equivalent to RGB code 660099.
| *000* | 300 | 600 | 900 | C00 | *F00* |
| *003* | 303 | 603 | 903 | C03 | *F03* |
| 006 | 306 | 606 | 906 | C06 | F06 |
| 009 | 309 | 609 | 909 | C09 | F09 |
| 00C | 30C | 60C | 90C | C0C | F0C |
| *00F* | 30F | 60F | 90F | C0F | *F0F* |
| 030 | 330 | 630 | 930 | C30 | F30 |
| 033 | 333 | 633 | 933 | C33 | F33 |
| 036 | 336 | 636 | 936 | C36 | F36 |
| 039 | 339 | 639 | 939 | C39 | F39 |
| 03C | 33C | 63C | 93C | C3C | F3C |
| 03F | 33F | 63F | 93F | C3F | F3F |
| 060 | 360 | 660 | 960 | C60 | F60 |
| 063 | 363 | 663 | 963 | C63 | F63 |
| 066 | 366 | 666 | 966 | C66 | F66 |
| 069 | 369 | 669 | 969 | C69 | F69 |
| 06C | 36C | 66C | 96C | C6C | F6C |
| 06F | 36F | 66F | 96F | C6F | F6F |
| 090 | 390 | 690 | 990 | C90 | F90 |
| 093 | 393 | 693 | 993 | C93 | F93 |
| 096 | 396 | 696 | 996 | C96 | F96 |
| 099 | 399 | 699 | 999 | C99 | F99 |
| 09C | 39C | 69C | 99C | C9C | F9C |
| 09F | 39F | 69F | 99F | C9F | F9F |
| 0C0 | 3C0 | 6C0 | 9C0 | CC0 | FC0 |
| 0C3 | 3C3 | 6C3 | 9C3 | CC3 | FC3 |
| 0C6 | 3C6 | 6C6 | 9C6 | CC6 | FC6 |
| 0C9 | 3C9 | 6C9 | 9C9 | CC9 | FC9 |
| 0CC | 3CC | 6CC | 9CC | CCC | FCC |
| 0CF | 3CF | 6CF | 9CF | CCF | FCF |
| *0F0* | 3F0 | *6F0* | 9F0 | CF0 | *FF0* |
| 0F3 | *3F3* | *6F3* | 9F3 | CF3 | *FF3* |
| *0F6* | *3F6* | 6F6 | 9F6 | *CF6* | *FF6* |
| 0F9 | 3F9 | 6F9 | 9F9 | CF9 | FF9 |
| *0FC* | *3FC* | 6FC | 9FC | CFC | FFC |
| *0FF* | *3FF* | *6FF* | 9FF | CFF | *FFF* |
Safest web colors
Designers were often encouraged to stick to these 216 "web-safe" colors in their websites; however, 8-bit color displays were much more common when the 216-color palette was developed than they are now. David Lehn and Hadley Stern have since discovered that only 22 of the 216 colors in the web-safe palette are reliably displayed without inconsistent remapping on 16-bit computer displays. Highcolor graphics (variously spelled Hicolor, Hicolour, and Highcolour, and known as Thousands of colors on a Macintosh) is a method They called these 22 colors the "really safe" palette; it consists mainly of shades of green and yellow, as can be seen in the table above, where the "really safe" colors are underlined. [9]
CSS colors
The Cascading Style Sheets language defines the same number of named colors as the HTML 4 spec, namely the 16 listed previously. Web colors are Colors used in designing web pages and the methods for describing and specifying those colors Additionally, CSS 2. 1 adds the 'orange' color name to the list:
| Color | Hexadecimal |
|---|---|
| orange | #FFA500 |
CSS 2, SVG and CSS 2. The colour orange occurs 1 also allow web authors to use so-called system colors, which are color names whose values are taken from the operating system. An operating system (commonly abbreviated OS and O/S) is the software component of a Computer system that is responsible for the management and coordination This enables web authors to style their content in line with the operating system of the user agent. [10] As of early 2004, it appears that the CSS3 color module will once again drop these values, marking them deprecated, but this may change. "MMIV" redirects here For the Modest Mouse album see " Baron von Bullshit Rides Again " In Computer software standards and documentation the term deprecation is applied to Software features that are superseded and should be avoided [11]
The developing CSS3 specification will also introduce HSL color space values to style sheets:
/* RGB model */
p { color: #F00 } /* #rgb */
p { color: #FF0000 } /* #rrggbb */
p { color: rgb(255,0,0) } /* integer range 0 - 255 */
p { color: rgb(100%, 0%, 0%) } /* float range 0. HSL and HSV are two related representations of points in an RGB color space, which attempt to describe perceptual color relationships more accurately than 0% - 100. 0% */
/* RGB with alpha channel, added to CSS3 */
p { color: rgba(255,0,0,0. 5) } /* 0. 5 opacity, semi-transparent */
/* HSL model, added to CSS3 */
p { color: hsl(0, 100%, 50%) } /* red */
p { color: hsl(120, 100%, 50%) } /* green */
p { color: hsl(120, 100%, 25%) } /* light green */
p { color: hsl(120, 100%, 75%) } /* dark green */
p { color: hsl(120, 50%, 50%) } /* pastel green */
/* HSL model with alpha channel */
p { color: hsla(120, 100%, 50%, 1) } /* green */
p { color: hsla(120, 100%, 50%, 0. 5) } /* semi-transparent green */
p { color: hsla(120, 100%, 50%, 0. 1) } /* very transparent green */
Accessibility
- Some browsers and devices do not support colors. A web browser is a software application which enables a user to display and interact with text images videos music games and other information typically located on a
- For blind and colorblind users, Web content depending on colors can be unusable or difficult to use.
- Mixing legacy markup like bgcolor with modern CSS fails for legacy browsers not supporting CSS.
- Both foreground and background color should be modified to avoid black on black effects.
Popular browsers show links as shades of blue. Dark background colors, such as blue or navy, do not display well for such links. Using CSS to modify link colors does not work with legacy browsers. For example, in Netscape 4. x support for CSS is frequently disabled for being rather paltry.
See also
References
- ^ CSS3 color module
- ^ RGB to Hexidecimal Color Converter
- ^ HTML 4.01 Specification section 6.5 "Colors"
- ^ HTML 3.2 Specification "The BODY element"
- ^ Public discussion on SVG mailing list Re: color names in SVG-1.0 conflict with /usr/lib/X11/rgb.txt
- ^ W3C TR CSS3 Color Module, SVG color keywords
- ^ W3C TR SVG 1.0, recognized color keyword names
- ^ Fu, A. A Color tool is an application usually found within Graphics software and online used for the purposes of Color management, creating Color schemes picking The following is a partial list of Colors with associated articles. et al, Anti-Phishing Coloring Scheme, Hong Kong, 2006
- ^ Death of the Websafe Color Palette?
- ^ User interface - System colors
- ^ CSS3 Color Module - CSS2 System Colors
External links
- CSS2.1 Color Specification
- HTML Color Spectrum Chart (Chromas/Achromas)--Lists chromatic and achromatic colors (no tints or shades)
- 4096 web colors & hexadecimal codes produced by combining 16 shades of each primary color (Red, Green & Blue)
- Html Color Codes Dynamic html color codes chart and color picker
- X11, HMTL, WEB colors Color wheel and Color picker that includes categorized colors described in this article
- Web-Safe Color Demo using the Color Picker in Adobe ImageReady. “Tint” redirects here For other uses see Tint (disambiguation In Color theory, a tint is the mixture of a Color with Shade is the blocking of Sunlight (in particular direct sunshine by any object and also the Shadow created by that object
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