Google recently sent out 100,000 stickers to selected US businesses for use on their storefront windows. The stickers have the Google Maps logo and a QR (Quick Reference) code that can be scanned by smart phone cameras and display Google listings for the business on the phone screen.
A camera is often included in mobile phones, portable gaming devices and PDAs, so rather than laboriously copy down the details, these 2D bar codes provide a quick way to transfer simple information.
You can generate your own bar codes at the QR-Code Generator website. To read them, you’ll need an application linked to your camera. Try search your ‘phone’s application store, or take a look on google for QR Code reader