This day in Bar Code History:

On October 7, 1952 Joseph Woodland and Bernard Silver received the first patent for a bar code product. Their device was the size of a desk and included a 500 Watt incandescent light bulb. We’ve come a long way! Check out the patent here.

Sources:
http://www.cs.iusb.edu/internship/papers/laslo/Bar_Code.html
http://inventors.about.com/library/inventors/blbar_code.htm