Light coming from the sun is made up of a spectrum of wave lengths, a narrow band of which makes up visible light and hence, visible color. Theater lighting, television screens, computer monitors and HTML color schemes are all based on a model which mimics how we see color in the real world. Assuming one isn't color blind, one has two methods of seeing: rods and cones. The rods in the back of the eye control how one sees light and dark and by themselves would produce a grayscale image. The cones are divided up into three types: red, green and blue. Click here for more information. In keeping with that model, the primary colors are defined as Red, Green and Blue.

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Web pages use and RGB color scheme converted to a hexidecimal (base 16) system to render colors. The color scheme starts with a pound sign and is then followed by six numbers. The first two are the Red Channel, the second two are the Green Channel and last two are the Blue Channel. "Web safe" colors are done as pairs of letters in each channel, selecting from these values: 0, 3, 6, 9, C, F. 00 is the lowest value per channel, so that #000000 makes the color black. FF is the heighest value so that #FF0000 is red, #00FF00 is green, #0000FF is blue and #FFFFFF is white. The color gray is made when all three channels have the same value, assuming that value is between 00 and FF. If you have a graphics program such as Photoshop or Freehand, you can do your color selection there and have the program tell you what the values are. Most WSYWYG HTML editors will also have the websafe pallet on hand.

For more information regarding web safe colors, I recommend these links:

• Color Table organized by Hue
• Color Table oraganized by Value
• Color Table with explanation and history