Color can be broken down into Hue Saturation and Value/Brightness to make the color scheme more logical.
Think of Hue is a wheel is broken into 360 colors - one for each degree of the circular wheel.
The hue color wheel goes from red through yellow to green through cyan to blue and through majenta back to red as shown below.http://upload.wikimedia.org/wikipedia/commons/f/f4/Color_circle_(hue-sat)_trans.png
At 100% saturation and 100% value/brightness the color is what you may call "full color", like the outside of that circle. If you want to make it darker, change the value/brightness to a lower value. To make it washed out then change the saturation to a lower value. Zero value/brt is black. Zero saturation is white or gray depending on value/brt.
You can use the following calculator to get the degree from the color wheel and plug it in. Use 100 for saturation and 100 for value/brightness and enter a color value from 1 to 360 and you will get the RGB value for any color.http://www.csgnetwork.com/csgcolorsel4.html
Hope that helps.