The birthday of Scientist, John Dalton is celebrated as Colour Blindness Awareness Day to raise awareness of people with colour blindness. After discovering his own colour blindness, he began conducting rudimentary tests on his friends to see if they shared his colour vision impairment. His observations contributed to the discovery of what we now call colour vision deficiency (CVD) or more commonly known as colour blindness.
For most colour blind people their condition is genetic, usually inherited from their mother, although some people become colour blind as a result of other diseases such as diabetes and multiple sclerosis or it can be acquired due to ageing or from taking drugs and medications.
Although considered only a minor disability, slightly fewer than 10% of all men suffer some form of colorblindness (also called color deficiency), so this audience is very widespread. Colorblind users are unable to distinguish certain color cues, often red versus green.