In February 2015, a photo of a striped dress posted online unexpectedly turned into a worldwide argument. Some viewers swore it was blue and black, while others were convinced it was white Black Blue Yellow White Dress Black The Blue And White Dress Illusion Illusion Yellow Blue Remember when the internet went absolutely nuts on the colour of a dress? The dress was blue and black. The original viral poster, Caitlin McNeill, later said it was a black and blue dress ELI5:Why does this dress appear white gold to some people and black blue to others? : r explainlikeimfive