Imperative visual data frequently vanishes when color applications are seen by partially color blind users.
Navigation should stand out from the content and visitors should be able to quickly differentiate between the two.
Contrasting colors or colors on the opposite ends of the color spectrum work best for color blind users (e.g., white and black is the best example).
It is considered a best practice to use bright colors.
People who have color deficiencies can see all the colors but they have a problem differentiating between them so using bright, bold colors helps.
The are several reasons: 1) a site should always strive to be user-friendly for all audiences 2) there are standards that keep sites accountable to people with disabilities and 3) well-designed sites don’t require changes to make the accessible. Computerized simulation of color appearance for dichormats.
Improving the site for color-blind individuals has an affect on other populations as well.
Image maps have clickable areas that are often delineated by color.
Options are to add underlined text to the clickable areas or a black outline around the images (e.g., outline around a state on a map).
Color blindness is the inability to perceive differences between some of the colors that non-colored impaired users can distinguish (Wikipedia).