In a Data Matrix code, the information is encoded in compact form as black and white cells arranged in a square or rectangular pattern. Hence, a Data Matrix code, when scanned, does not involve the differentiation between two different bar widths (as in the case of 1D linear code).
The Data Matrix consists of identically-sized contiguous black and white rectangles (or sometimes circles) within the matrix pattern. The uniform symbol size and equal distances between them make it much easier to scan the image and decode the information while also ensuring that the code itself can be kept very compact.
The Data Matrix code is today the most familiar of the 2D codes and is employed, among other things, for the direct marking of products for production and logistical purposes by means of laser and inkjet printers.
As the Data Matrix code provides the opportunity to correct encoding errors, it is slowly replacing barcodes as these latter only allow error recognition. The Data Matrix code also consists of redundant data so that with the help of the Reed-Solomon code for error correction (ECC 200) up to 25% of the errors in individual elements can be automatically corrected if, for example, parts of the code have been concealed or obliterated.