The dress was a 2015 online viral phenomenon centred on a photograph of a dress. Viewers disagreed on whether the dress was blue and black, or white and gold : r wikipedia The Dress Debate: White and Gold or Blue and Black? 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, so we know the dress was black and blue BUT that's not what i'm here to discuss : r opticalillusions How "The Dress" Became an Illusion Unlike Any Other Scientific American Blue or Gold? How the brand behind #TheDress monetised viral success