Eyes are miraculous contraptions! When light goes through the lens at the front of your eye, it travels back to a projection screen called your retina which is packed tightly with a fat layer of cells made up of rods and cones.
Rods allow you to see in black and white in dim light. It’s cones, on the other hand, which provide the color in bright light. Cones come in different pigments and it’s these pigments which enable you to discern different colors! Being color-blind doesn’t mean you see everything in black and white. It just means that you may be missing particular color cones, such as red and green cones. If you are, red and green will look gray, but other colors will be just fine. While most commonly color-blindness affects seeing red and green, some people are unable to see blue and/or yellow.
Men seem to be affected by color-blindness more than women but doctors don’t know why. Approximately 1 out of every 12 men has some kind of color blindness!
Answer provided by Discovery.com