What you see below is called a QR code and it’s used for Android user as a quick way to get link to online content or if you want to install an Android app. In order to use QR codes you need to use your phone camera. This way you can save lot of your time typing lengthy URL addresses into your mobile browser.
QR Code Barcode Scanner
A QR Code is basically a two-dimensional code (specifically a matrix barcode) readable by camera phones and dedicated QR barcode readers. 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.
How to use your QR codes with your Android phone
You need to first install barcode reader app or bar code scanner from android market. Once installed, run barcode scanner app on your Android phone and point your camera at a QR code. It will automatically show you the download section in the Android Market. You can try by scanning the above QR code and see where it takes you in Android market.