QR is short for Quick Response because these codes can be read quickly by a cell phone, a smart cell phone that is, and give you access to detailed information. Although it might not tell you the outcome of your history quiz, it can be configured to take you to chapter highlights.
You've probably seen these intricately marked squares (look right to see one I created) and wondered what they are. Basically QR codes are a special type of bar code. They are a mobile tagging device that can store much more data than a standard bar code including url links, geo coordinates, text, really any kind of information that can be stored digitally on the Internet.
They make everything interactive so you'll see them being used in stores next to merchandise, on business cards where contact information magically downloads, on posters detailing event information or billboards where they reveal a secret, on T-shirts perhaps expanding on a theme or even on TV.
It all started in Japan where QR codes were created for use in vehicle manufacturing and gained rapid adoption and then broke into Europe. They are gaining popularity in the US as we too become a nation of smartphone users. According to a Nielsen study, 50% of US mobile subscribers (or 142.8 million people) will be smartphone owners this year.
If you're one of these lucky smartphone users, you can download the QR code reader app (from a site like Kaywa or ScanLife) and start scanning. And you should because these mysterious rorschach squares can transport you to all types of information including coupons, product information, event details, a explanatory YouTube video, Facebook fan page, or even your daily horoscope.
So you will be able to find out about your love life after all! Bottom line, a QR code is a consumer portal to more information, so the advertising can stay succinct while the offer details, if you're curious, are easily accessible.
Want to know more?
Why Haven't You Started Using QR Codes
How QR Codes Can Grow Your Business
Separating Trend from Fad with QR Codes in Social Media
Stickerscan latest articles on QR Codes and NFC technologies
15 Beautiful and Creative QR Codes (added 7-23-2011)
Picture from Wikipedia article on Paper Fortune Tellers
June 11, 2011 - Addendum: Here's a great article from a source I trust on Why Marketers Shouldn't Waste Their Time with QR codes but I still think they have a place plus they're fun.