(MILTON, Del.)- What started as a simple question, turned into a debate by millions.
It was originally posted by a user on Tumblr, spreading like wildfire on social media.
Some people see it as blue and black, others seeing white and gold.
"It's the processing that the brain is doing," said Dr. Karen Rudo, Delaware Eye Clinics. "Comparing the actual dress to the background, it's really the way the photography is done that we interpret the image."
The photo became so popular, there were multiple trending topics on Twitter.
'#TheDress' has been trending on twitter for more than 12 hours, with more than 1.4 million uses.
Color blindness and emotion were being blamed as the reason for the divide.
It's really an optical illusion, we shouldn't be worried about.
"In our day-to-day lives there is really no effect, because this is how we see," said Rudo. "So it's really a beneficial thing that our brain is able to do this unconcious thinking."
With all the publicity the dress is receiving, the brittish clothing store, Roman Originals, has restocked the dress.
The dress is selling for 50 Brittish pounds which is equivalent to $77 US dollars.
