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, The dress: Celebrities join the white and gold or blue and black debate Daily Mail Online Blue color net gown with golden work Panache Haute Couture The actual dress was black and blue. The confusion came from how lighting and color perception tricked people's brains, making some see it as white and gold. It became a viral example Proof the Dress Is Blue PS Tech