QR codes (Quick Response) are a type of bar code that is often used in online purchases; specifically items like sporting tickets stored on mobile phones. As one enters an arena, the code is scanned from a mobile device, and voila, you are in.
Exactly why the Dutch mint has decided to add them to coins is beyond me, but according to the press release:
Quick-Response matrix barcode which once scanned using a smartphone will take them to the Royal Dutch Mint website where there'll be a "surprise" awaiting them.
That surpise, may just be a record of where and what your coin has been doing.
