QR Code (QR stands for Quick Response) is a two-dimensional code that can be read by QR scanners, camera phones, and smartphones. It was created in 1994 by Denso Wave, a subsidiary of Toyota.

QR codes can handle all types of data (see table below).

Numeric mode:0123456789up to 7089 characters
Alphanumeric mode:ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 $%*+-. / : spaceup to 4296 characters
Binary mode (8-bit byte data):JIS 8-bit (Latin, etc.)up to 2953 bytes
Kanji mode:Shift JIS (8140H-9FFCH and E040H-EBBFH)up to 1817 characters

QR Code Features:

Barcode size (not including quiet zone): 1 to 40 versions (21 * 21 modules to 177 * 177 modules, increasing by 4 modules per side)

Recovery is possible with the 4-step correction function:

Correction levelPercentage of information recovered
L.7%
M.15%
Q.twenty five%
H.30%

 
The higher the level of error correction, the greater the percentage of lost barcode information that can be recovered, but the less information that can be encoded in the same size barcode. The image below is an example of a QR code.

"QR code" barcode.