[ Thanks to DIPIN for this link. ]
“A QR
code (it stands for “Quick Response”) is a mobile phone
readable barcode.simply encode a URL into the QR Code and then
point a mobile phone (or other camera-enabled mobile) at it. If the
device has had QR Code decoding software installed on it, it will
fire up its browser and go straight to that URL.“But it doesn’t stop there – a QR Code can also contain a
phone number, an SMS message VCard data or just plain alphanumeric
text, and the will respond by opening up the correct application to
handle the encoded data appropriately courtesy of the FNC1
Application Identifiers that are embedded in the encoded data.“The technical specifications for a QR Code are set down in the
ISO-18004 standard so they are the same all over the world, and the
only significant variations from one QR code to another (apart from
the data it contains) is the number of modules required to store
the data.”