Edwin Land was having a better time on his Grand Canyon vacation than his daughter. They were walking through Santa Fe, New Mexico, when the three-year-old asked why she could not right away see the photo he took of her. Her question stuck with Land: he already had good knowledge of photography and chemistry, and spent the rest of the day conceiving of a system that would instantly show the photograph taken.
On this day, February 21, in 1947 Edwin Land first demonstrated his invention, named Polaroid for the polarization of light principle that enabled instant picture exposure.
After spending a year tuning up and perfecting the Polaroid, Land put fifty-odd units on sale for the Christmas holiday at the Jordan Marsh department store in Boston. He expected them to be bought only gradually, allowing him time to gauge customer demand and manufacture more to put on the shelves. All were sold before the store closed for the day.