When the word “colorblind” is brought up, one might be tempted to think of old black-and-white movies and equate color blindness to the lack of being able to see any color. And while there is one, very rare form of color blindness that resembles this (known as monochromacy), the majority of colorblind people can still see color; however, they usually see certain colors on the color spectrum differently. There are multiple kinds of color blindness, the most common being red/green color blindness, followed by blue/yellow color blindness, according to iristech.co. 

Color blindness is caused when certain cones in the retina are defective and don’t respond to light wavelengths correctly. For example, in red/green color blindness, the L cones, which are responsible for distinguishing red and green wavelengths, are either missing or deficient. There are a few main forms of red/green color blindness. According to the National Eye Institute, deuteranomaly is the most common type of color blindness, where green looks more red. Protanomaly is another form where red looks more green and less bright. Having both protanopia and deuteranopia makes one unable to distinguish reds from greens completely. 

The other common form of color blindness, blue/yellow color blindness, is caused by missing or mutated S cones, and has two main forms: Tritanomaly, which makes it hard to tell the difference between blue vs. green and yellow vs. red, and tritanopia, which makes it hard to tell blue vs. green, purple vs. red, and yellow vs. pink (the colors are also dimmed).

Color blindness is primarily a genetic condition. Red/green color blindness is inherited on the X chromosome of chromosome 23, which also determines a person’s sex. Because of this, red/green color blindness is considered a sex-linked disease and more males are red/green colorblind than females, according to nei.nih.gov. Blue/yellow color blindness is inherited on a different chromosome, so unlike red/green color blindness, it affects males and females equally. 

Color blindness can also occur as a result of a disease or injury that affects the eyes or brain. There is no cure for color blindness, though special glasses or contacts may help certain individuals see variants in their colorblind colors.

Below are sliding images that show how a colorblind person might view a certain color depending on the type of color blindness they have. All colors were generated from coolors.co and venngage.com.