So you are thumbing through a magazine and stumble upon an ad that includes a postage-stamp sized graphic with a black & white interlaced pattern. What’s this?
You wonder if it is a close-up view of some image, so magnified that only a few square pixels are in view. Actually, the graphic is an image of data. It is simply a two-dimensional barcode, just waiting to be accessed — using your cell phone! Read more… →