I always seem to come back to these. Essentially a QR-Code can be a URL, Text, Phone Number or an SMS. A modern camera mobile phone is needed to translate the code, these are becoming more and more ubiquitous.

Pepsi who have recently rebranded are using 400 million QR-Codes as part of their digital strategy. Link.
Also Ralph Lauren is also adopting the QR-Code for use with it’s online and phone shopping experience.
Link.

Not only are these brands paving the way forward with this technology but they are also paving the way for phone, web and ‘real-world’ interactions. There has been a big uptake recently especially in the youth market.