Do you know what is QR Code?
A QR code (short for Quick Response) is a specific matrix barcode (or two-dimensional code), readable by dedicated QR barcode readers and camera phones. The code consists of black modules arranged in a square pattern on a white background. The information encoded can be text, URL or other data.
Was checking a barcode reader and found that app that i was testing can read QR codes so this was it.
Here is a QR code of my Kannada greetings site.
These are easily readable by most smartphones with camera by installing small app.