So I did a bit of research, and I found out that those ‘square-shaped’ barcodes are actually called QR Codes, a 2-D symbology created in 1994 by a Japanese company called Denso Wave (more here). The principle is the same as a barcode, except that if a barcode contains data only on the horizontal axis (the bars) the QR codes organize them on both horizontal and vertical axes (which means an exponential increase in volume of information).
Also, the idea of ‘hardlinking‘ between real world and digital contents is at the base of the Semapedia project
Our goal is to connect the virtual and physical world by bringing the right information from the internet to the relevant place in physical space.
To accomplish this, we invite you to create Semapedia-Tags which are in fact cellphone-readable physical hyperlinks. You can create such Tags easily yourself by choosing and pasting a Wikipedia URL into the form above. Once created, you put the Tags up at their according physical location. You just hyperlinked your world! Others can now use their cellphone to ‘click’ your Tag and access the information you provided them.
Basically, create a QR code that contains a Wikipedia link, print it, and stick it somewhere in the real world. For example
If walking by the Zurich lake you want to know more about it, whip your smartphone out, scan the QR code and you are addressed to the relevant Wikipedia page (to see more exemplifying pictures, just look for the ‘semapedia’ tag on Flickr). The fact that I find this idea so exciting is somewhat worrying.
Finally, there are websites that help you create your own QR code. Here for example you can create your own with an hyperlink
[the hyperlink for this blog]
or up to 250 characters of text. Going back to my idea of tagging books with these codes containing keywords, here is an example:
This one contains keywords about a recent and very popular philosophy book (scan it to find out what). It is about 180 characters, and you can see that the pattern becomes much more complex (and the scanning time is also a bit longer) as compared to the hyperlink one. I wonder if it would be possible to create one with a meaningful text and whose pattern of pixels reproduces some kind of image.
I think that soon I will begin my book-tagging project. After that, I could write my whole thesis in QR codes.
EDIT: Looks like someone on Flickr already had this idea! (it’s a hyperlink, not text with keywords though).