colors

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Color can be used to add an extra dimension to the content of a page, but selection of colors on web pages goes a little further than just the aspect of design. Not everyone viewing a page has the same hardware, and therefore the number of colors may be limited. This has to be taken into account when using colors in web pages.

Note that setting colors is merely an advice to the browser, and may be ignored or interpreted rather liberally, upto the point that different colors are actually selected. This may even happen on this page!

RGB

Describing colors unambiguously is done as follows. The color model used in HTML is RGB, for red-green-blue, and can take values of 0 - 255 for each of these. The tricky part is that these values aren't written in decimal, but hexadecimal, which is a numeric system with base 16. Since arabic numbers only allow 10 different values, the letters A-F are added to these. So counting in hexadecimal goes

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F, 10, 11, ...
Values from 0-255 decimal can be expressed in two digits hexadecimal: 00-FF. In HTML, a color is specified as #RRGGBB, in which the RR, GG, and BB specify the red, green and blue values. Examples:

named colors

It is also possible to use named colors in stead of specifying the red, green and blue values, but the definition of a named color is not guaranteed to be same for all hardware, nor can it be assumed to be supported by all browsers. Therefore, the safest way is to specify colors as described above. Still, for those who prefer named colors, the list below appears to be reasonably well supported by the popular browsers.

color	value	name		color	value	name		color	value	name		color	value	name
	#000000	Black			#800000	Maroon			#008000	Green			#000080	Navy
	#808080	Gray			#FF0000	Red			#00FF00	Lime			#0000FF	Blue
	#C0C0C0	Silver			#800080	Purple			#808000	Olive			#008080	Teal
	#FFFFFF	White			#FF00FF	Fuchsia			#FFFF00	Yellow			#00FFFF	Aqua

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