Read all about QR Code
http://en.wikipedia.org/wiki/QR_Code
Get a QR Code scanner for Android
https://market.android.com/details?id=la.droid.qr&hl=en
Get a QR Code reader and scanner from iTunes
http://itunes.apple.com/us/app/qr-code-reader-and-scanner/id388175979?mt=8
Get a QR Code reader for Java, Symbyan or Win Mobile
http://reader.kaywa.com/