CMYK and RGB color code in TeX

I found that control coloring in TeX is not an easy task.  Sometimes, you want your font to be colored as brown.  But brown is not explicitly defined in the color package.  I found a web page that provides detailed color pallet with the color name and the CMYK and RGB setting.

Here is the link to the webpage.

http://www.december.com/html/spec/colorcodes.html

So you can look up the percent code of CMYK or RGB in this webpage and define the color in TeX as the followings:

1. Call the package color

\usepackage{color}

2. Define the RGB color

\definecolor{brown}{RGB}{128,42,42}

or

\definecolor{brown}{cmyk}{0,0.67,0.67,0.50}