Some people have a genetic condition that allows them to see nearly 100 million colors.

Researchers estimate that some 300 million people around the world are colorblind, most of them male. On the opposite end of the spectrum are those with an exceedingly rare genetic condition that allows them to see nearly 100 million colors — or 100 times as many as the rest of us. It’s called tetrachromacy, or “super vision,” and it’s the result of having four types of cone cells in the retina rather than the usual three. (Cones help our eyes detect light and are key to color vision.) Because of the way the condition is passed down via the X chromosome, the mutation occurs exclusively in women. One tetrachromat describes her ability this way: “If you and I look at a leaf, I may see magenta running around the outside of the leaf or turquoise in certain parts where you would just see dark green. Where the light is making shadows on the walls, I’m seeing violets and lavenders and turquoise. You’re just seeing gray.” In short, tetrachromats see colors within colors, and even the tiniest change in the color balance of a particular hue will be apparent to them. It's estimated that 12% of women have a fourth retina cone, but only a fraction of them experience tetrachromacy. In total, only about 1% of humans have the condition. The rest of us will just have to close our eyes and imagine what it’s like.