A QR Code (quick response)  is a two-dimensional bar code created by Japanese corporation Denso-Wave in 1994. Initially used for tracking parts QR codes are now used in a much broader context, including both commercial tracking applications and convenience-oriented applications aimed at mobile phone users (known as mobile tagging). 

QR codes storing addresses and URLs may appear in magazines, on signs, buses, business cards or just about any object that users might need information about. Users with a camera phone equipped with the correct reader software can scan the image of the QR Code causing the phone’s browser to launch and redirect to the programmed URL. 

Users can also generate and print their own QR Code for others to scan and use by visiting one of several free QR Code generating sites.

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