A QR Code is a matrix code (or two-dimensional bar code) created by Japanese corporation Denso-Wave in 1994. The “QR” is derived from “Quick Response”, as the creator intended the code to allow its contents to be decoded at high speed.

QR Codes are common in Japan, where they are currently the most popular type of two dimensional codes. Moreover, most current Japanese mobile phones can read this code with their camera.

Although initially used for tracking parts in vehicle manufacturing, 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. This act of linking from physical world objects is known as a hardlink or physical world hyperlinks. Google’s cellphone OS Android heavily uses QR codes.

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.

The use of the QR Code is free of any license. The QR Code is clearly defined and published as ISO standard. Denso Wave owns the patent rights on QR Code, but has chosen not to exercise them.

The term QR Code itself is a registered trademark of Denso Wave Incorporated.

A huge billboard advertisement in Shibuya (Tokyo, Japan). A pedestrian may use a cellphone to read the QR code (barcode) with the phone’s camera. The phone will open a web browser to the URL encoded in the QR code.

Something surprising is that the ad consists of the QR alone, meaning that the public will open the web page out of curiosity. The support seems to be a LCD but the image is static, no animation.