Eleven years ago, a single photo posted on Tumblr sparked one of the biggest internet debates of all time. The dress instantly divided the world, some swore it was white and gold, In 2015, a photograph of a dress went viral, dividing viewers over whether its colors were blue and black or white and gold. This optical illusion highlighted differences in human color perception Is That Dress White and Gold or Blue and Black? The New York Times TheDress: What's the science behind its true color? CSMonitor.com