Link technology allows users to include links to rich digital content in their printed documents. Users can create digital watermarks, QR codes, and short URLs to add to their posters, labels, business cards, invitations, flyers, and any other printed items. Digital watermarks and QR codes can be scanned by mobile devices to take people directly to linked digital content. The Link Developer API allows users to create watermarked images, short URLs, and QR codes and analyze their traffic. The API also lets users update the destinations linked to by watermarks and QR codes anytime, even long after they have been created and printed.