A QR Code system is used in combination with a QR Code printer(or QR Code creation software) and QR Code scanner. QR Code is generated with QR Code creation software and a special printer. 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-code features
QR Code provides the following features compared with conventional bar codes.:

High Capacity Encoding of Data
QR Code is capable of handling several dozen to several hundred times more information than a bar code which has a maximum limit of almost 20 words. numeric and alphabetic characters, Kanji, Kana, Hiragana, symbols, binary, and control codes can be handled by the QR code.

Small Printout Size:
QR Code is capable of encoding the same amount of data in approximately one-tenth the space than conventional bar code.

Kanji and Kana Capability:
For Japanese letters, one full-width Kana or Kanji character is efficiently encoded in 13 bits

Dirt and Damage Resistant
It has error correction capability. Data can be restored even if the symbol is partially dirty or damaged.

Readable from any direction in 360°:
QR Code is capable of 360 degree (omni-directional), high speed reading

Structured Append Feature:
information stored in multiple QR Code symbols can be reconstructed as single data symbols.

for more details, visit:
http://denso-waveqrcode/qrfeature-e.html
http://en.wikipediawiki/QR_Code