This is the Winning Entry for a Contest to Explain Colour

Every year, Alan Alda holds a science communication challenge, posing surprisingly tricky questions and asking for answers appropriate for elementary school audiences. This year's question was, "What is colour?" and Dianna Cowern produced the winning video.

To learn more about Dianna Cowern, a physicist who has been producing videos as Physics Girl for the last few years, check out this interview on Scientific American's PsiVid.