QR Codes is an interesting way of storing & exchanging text information inside images.
These black & white images may make no sense to the human eye but the information contained inside the image can be extracted instantly on the desktop or a mobile phone using free decoders.
For instance, the QR coded image above stores the login details of a fictional bank account. That information can be easily extracted by passing this image through a QR code decoder application as shown here.
Advantages of QR Codes
Unlike the more popular bar codes, a QR Code stores data in both the vertical and horizontal directions and hence have more storage capacity per unit area.
Denso Wave, the company that introduced QR Codes to the world, says that QR codes are readable from any direction and that data stored inside QR codes can be restored even if the corresponding image is partially damaged.
How people use QR Codes
For instance, some companies put their web addresses as a QR code in print ads - people then just click that page with their cell phone cameras and then can visit the advertisers’ website directly without typing anything because the mobile software will decode the image.
How to create QR Code
If you like to make your own QR Codes, go to Kawya - a web based QR code image generator. Now to decode these QR images, download a small Java app for desktop or get this reader if you have a Java enabled mobile phone like Nokia, Sony Ericsson, etc.
The Chart API in Google also supports QR Codes so you may convert any piece of text or hyperlink into an QR image just by writing simple URLs. Alternatively, you may create a Google Short URL and add .qr to the URL.
Related: Hide Documents Inside JPG Images