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 growing in popularity in the U.S. and being adopted by libraries. One article on the subject is:
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.
Walsh, Andrew. Quick response codes and libraries. Library Hi Tech News. v. 26, n. 5/6. p. 7-9. (If you have access to the Emerald database, you can find the article there.)There could be many uses of QR codes in libraries. For example, using a camera phone with a mobile browser and free QR code software, a patron could use a QR code on a bookshelf to locate and read a related guide on the subject (libguide).
At Computers in Libraries, QR codes were created for all of the bloggers and placed on the bulletin board. These became conversation starters because most people have never seen them or used them. And people could try them out in a safe environment. (JD, nice idea!)