A Data Matrix code can store a large amount of data, with up to 3116 numbers. The code is powerful because of the redundancies built into its encoding. Typically, around 30% of a Data Matrix can be damaged and all of the data still retrieved. This means that, during manufacture, simply being able to read a code does not ensure that it has been made 100% accurately - some of the redundancy might already have been used up and further damage will render the code unreadable.
After the code has been applied, data matrix verification provides a report on the quality of the mark and ensures that it will still be readable after further manufacturing processes, the product's life cycle or damage to the code.