10 years since THE DRESS blew up Internet. Two thirds of people saw white and gold. Its an optical illusion caused by weird lighting and an overexposed background. It Is actuallylly blue and black. 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 The Dress: Black, Blue, White, GoldA Visual Illusion as America Dies Here's why people saw the dress differently.