According to wikipedia -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.
Love the concept and till recently didn’t know the name for this ,even though I have encountered quite a few of these.The Code above was generated at http://qrcode.kaywa.com/ and is a QR code for this website.Its kind of retro cool like Morse Code which was most recently used by the Stig on Top Gear.
Makes for a great avatar photo if you are paranoid about putting your photo on the internet.It can also be used to store text,phone numbers etc.
Update:- If you want to decode QR codes these websites may come in handy
