Before you strangle your best friend who sees the colors in the now-famous dress differently than you do, please know that there's a scientific explanation.
It has to do with the tiny cones in the back of our eyeballs that perceive colors in a slightly different way depending upon our genes.
"Why do some people love cilantro and others say it tastes like soap? Why do some people have perfect pitch and others are tone deaf? It's the same with vision --- our sensory apparatus is fine tuned," says Dr. Julia Haller, the Opthalmologist-in-Chief at Wills Eye Hospital in Philadelphia.
The cones in our retinas --- the fine layer of nerve tissue that lines the back of our eyes --- detect the blue, green, and red in an image. The cones and your brain mix those colors to make other colors.
"Ninety-nine percent of the time, we'll see the same colors," Haller says. "But the picture of this dress seems to have tints that hit the sweet spot that's confusing to a lot of people."
The very top section of the dress appears gold to some people, but black to others.
This makes sense to Haller.
"One of the typical color confusions we see is blue/yellow," she says. "So perhaps in this dress, the black has a bit of blue and the gold has a bit of yellow."
For the record, Haller sees the dress as gold and white. But Dr. Anne Hanneken, an opthalmologist at the Scripps Research Institute in in La Jolla, California who's attending a conference with Haller, sees it as black and blue.
"She's looking at me right now like I'm nuts," Haller says. "She says, 'How could you possibly see it that way?'"
The picture was also being called a one-in-a-million shot by optometry experts in terms of of showing how dramatically different the human brain processes and perceives color and contrast, according to the Associated Press.
"This photo provides the best test I've ever seen for how the process of color correction works in the brain," Daniel Hardiman-McCartney, the clinical adviser to Britain's College of Optometrists, told the news organization. "I've never seen a photo like before where so many people look at the same photo and see two sets of such dramatically different colors."