QR Code

A QR Code (“Quick Response”) is a 2D barcode that can store much more information than a standard UPC. Inside a QR Code you can find text, hyperlinks, contact information, geo location, and more. They are capable of storing up to 250 characters.
One of the cool uses of QR Codes can be found via the share option in Barcode Scanner for Android. By pressing menu then share, users are able to easily send contact infomation, bookmarks, and text from their clipboard to other G1 phones.

This one contains Contact Information for Security Engineering.