Colours By name There are two different ways to specify a colour in a html document. The first is to use a name. There are a number of different colours that you can specify by name in a html document. A complete list of them can be found at http://www.geocities.com/~letslearnhtml/...
Hex The primary colours are red, green and blue. To create yellow you would have too combine red and green. To create magenta you would have to combine red and blue. To create aqua you would have to combine green and blue. To create white you would have to combine red, green and blue. There are 16.7 million colours that can be created by combining these three colours.
The reason there are so many is that the final colour differs depending on the amount of each colour that is used. For example if you use a certain amount of red and a certain amount of blue you will create a colour. If you double the amount of red that you used you will create a different colour.
But how do you tell the computer how much of each colour to use? You can use none of a certain colour, all of a certain colour or an amount in between. (NOTE: if you use all of every colour you will make white, if you use none of any colour you will make black). There are 256 different settings for each colour. For example you could set the red component to setting 200, the green component to setting 100, and the blue component to setting 50. This results in a dark orange colour.
Although in an image editing / creating program you specify colours in decimal. For example 34 bits of read, 67 bits of green and 123 bits of blue, where 34, 67 and 123 are all in decimal notation. On a web page you will use Hexadecimal notation. 34 becomes 22, 67 becomes 43 and 123 becomes 7B. To reference this colour in a html document you combine the three colours in order (IE: red, then green, then blue) and add a hash before it. The code for this colour would then be #22677B. This code could be used in any place where a colour is expected as a setting to attribute.
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