A two-dimensional bar code, or QR code, as they're known, made from black and white stones covers a sidewalk near the beach in Rio de Janeiro, Brazil, Friday, Jan. 25, 2013. The QR codes are being ... more 
A two-dimensional bar code, or QR code, as they're known, made from black and white stones covers a sidewalk near the beach in Rio de Janeiro, Brazil, Friday, Jan. 25, 2013. The QR codes are being placed at tourist spots which can be scanned with a mobile device for information about the site. (AP Photo/Silvia Izquierdo) less 
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Associated Press | Photo By Silvia Izquierdo
Fri, Jan 25, 2013 10:04 PM EST