Users of the internet search engine are being greeted with a bar code in place    of the usual Google    logo, exactly 57 years after United States inventors Norman Woodland and    Bernard Silver were granted a patent.  
 It follows recent Google    doodles in honour of the ancient    Chinese philosopher Confucius and Mahatma    Gandhi, the father of modern India.  
   Woodland and Silver, who met while students at the Drexel Institute of    Technology in Philadelphia, originally devised a system that would encode    data in concentric circles.  
 The lines of varying width were developed later, partly inspired by Morse    code.  
 According to a Washington Post report, the doodle bar code appears to    have been created by encrypting the word ‘Google’ using Code 128, a standard    symbology.  
 The original patent was filed by Woodland and Silver in 1949 and granted on 7    October 1952.  
 However, bar codes were not used commercially until retailers in the National    Association of Food Chains (NAFC) agreed on the familiar Universal Product    Code designs that are still seen on billions of worldwide items today.  
 The first supermarket scanner that could read UPC bar codes was installed at    March’s supermarket in Troy, Ohio, in June 1974. The first product to bear    the bar code was a packet of Wrigley’s chewing gum.  




















































