When I first accepted the offer to write QR Codes For Dummies, my initial thought was, “How am I going to write a whole book on QR Codes?” They are the simplest of digital tools. Writing about QR Codes was like writing about a screwdriver, another simple tool (that as of yet doesn’t have a For Dummies companion).

Sure, the numbers behind QR Codes are impressive. , one of the world’s leading websites for creating QR Codes, recently reported that 2.1 million users generated 2.7 million codes in 2011, an increase of 1,253 percent.

That’s a lot of QR Codes, and all from just one generator!

Still, probably a hundred times that number of screwdrivers are in every country in the world. So popularity wasn’t a good reason to write an entire book on QR Codes, or Screwdrivers For Dummies would’ve been a bestseller.

QR Codes are book-worthy because although screwdrivers are a tool for driving screws, a QR Code is highly versatile. They’re a key that unlocks something greater than expected and are a portal between the real world and the digital world. You can’t say that about a screwdriver.

QR Codes are simple tools that are powerful. They’re kind of like the ring Frodo Baggins carries in the trilogy The Lord of the Rings. They may be small and simple, but the ring and QR Codes are big medicine.

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