What are the datamatrix barcodes on letters?
I can't seem to find a satisfactory answer on google. Whenever I receive a bank statement, letter from my doctor, or utility bill, there are usually one or more Datamatrix 2D barcodes on it in varying positions on the page (where they would not be visible to the courier). What are these barcodes? Are they coming from some common software package used for content management? Are they used by a company that prints and sends letters?
They seem to be present on mail I have received in both the UK and US.
Some of them are there, I think, so that if you take a letter to a branch (remember those) or it is returned, there is a quick way of indentifying the source and authenticity and content of the letter without lots of effort. Ie why you were sent an offer for a stuffed goat from the utility company...
(UK stamps have codes on too, to reduce fraud I assume.)
In germany with the Deutsche Post, they are one way to stamp your mail and are used by the systems for the routing. Companies get access to the api and get the information the have to print on the package.
What information do they contain when you scan the data matrices?