First designed for the automotive industry in Japan, this matrix barcode is an optically machine-readable label "that is attached to an item and that records information related to that item. (Click here to learn more about QR Codes.)
The QR Code system has moved outside the auto industry because of its fast readability and greater storage capacity compared to standard UPC barcodes. They're used on websites but they're very useful on business cards, bookmarks, and other print media because the QR code can not only point to a website but also contain information -- sometimes a lot of information.
There are many websites that offer the QR code reader app for you to download as well as the ability to generate QR Codes. The one I use primarily is Kaywa. The website has FAQ and videos to instruct you, and it's all user-friendly.
Just register for a free account to begin. Your generated codes will be stored in your account. Then decide whether you want a "regular" QR Code or a Dynamic code.
Dynamic QR Codes are changeable. If you create one and need to change the information it points to, you just log onto your account, click on it, edit, and confirm. The very same QR Code will instantly lead to its new destination, with no reprinting necessary.
Use your imagination and try putting information in a QR Code in your next promotion.