The QR Code (Quick Response Code) is a 2-dimensional matrix code. It can encode up to 2509 numeric or 1520 alphanumeric characters and offers three levels of error detection. The smallest QR Code measures 21 X 21 cells (each cell encodes one bit) and can grow in increments of 4 cells to a maximum size of 105 X 105 cells. The squares in the bottom left, top left, and top right corners are locator patterns.
The QR Code has seen wide acceptance as the 2-D barcode of choice that can be scanned and decoded by virtually all smart mobile phones. Symbols can be used to encode web addresses, text message addresses, and other forms of contact information.
The QR Code was developed in Japan by the Nippondenso Company; it was introduced in 1994 at the Japan Scan-Tech show and was submitted to AIM for consideration as a standard in 1996.