2D / matrix codes
2D codes consist of polygonal, usually squarely arranged groups of data cells with a typical orientation symbol by which the code type can be recognized. Frequently used examples are the QR code and the Data Matrix code. See also Barcode.
2D codes have built-in error correction, which enables data to be recovered even if the code is damaged or dirty. Reed-Solomon error correction is used to restore the data.
Example of a QR code
