Common Features of 2D Symbologies

Both Data Matrix and QR Code symbols consist of a finder pattern, a data area, and a quiet zone. Data Matrix and QR Code symbols contrasts a Data Matrix symbol with a QR Code symbol:

Data Matrix and QR Code symbols

The finder pattern is used to locate, scale, and orient the symbol. As illustrated in Point locations in Data Matrix and QR Code symbols, three points uniquely define the finder pattern.

Point locations in Data Matrix and QR Code symbols

A 2D symbol has one of two polarities: light-on-dark or dark-on-light, as illustrated in Dark vs. Light Data Matrix symbols.

Dark vs. Light Data Matrix symbols

The symbol color is the inverse of the background color. White paper, for example, requires a dark symbol.

In symbols with dark-on-light polarity, data is encoded as follows:

A dark module represents a binary one.
A light module represents a binary zero.

Data Matrix and QR Code symbols can be produced in either continuous or dot-matrix formats. Continuous and dot-matrix formats illustrates Data Matrix and QR Code symbols produced in both formats:

Continuous and dot-matrix formats

The quiet zone for a continuous format symbol is one module wide for Data Matrix symbols, four modules wide for QR Code, Model 1 and Model 2 symbols, and two modules wide for Micro QR symbols. The quiet zone for symbols produced using the dot-matrix format is four modules wide. For more information about quite zones see the ISO specifications described AIM International Symbology Specification 97-001.