A better term for
Color Blindness would be Color Vision Deficiency. Rarely are people completely
colorblind, unable to see any color at all.

 Color Vision
Deficiency is the decreased ability to see color differences under normal
lighting conditions. Color blindness occurs because the color-sensitive cones
are either absent or do not work properly.

If you can see the
number 7 in the image (below), it’s because your eye’s green cones work properly.

A person whose red cones
are either lacking or not working properly sees an abnormally strong green
picture.

Color blindness affects
only about eight percent of all people, mostly males, and it is usually
inherited.

Color blindness is
usually classified as a mild disability; however there are occasional
circumstances where it can actually be an advantage. Some studies conclude that
color blind people are better at penetrating certain color camouflages.

Such findings may give
an evolutionary reason for the high prevalence of red-green blindness.

There is also a
study suggesting that people with some types of color blindness can distinguish
colors that people with normal color vision are not able to see.

Several well known
artists were color blind, including Australia’s Clifton Pugh and the French
artist, Charles Meryon.