Here's what Wikipedia says about QR Codes:
The QR code was invented in Japan by the Toyota subsidiary Denso Wave in 1994 to track vehicles during manufacture. It was designed to allow high-speed component scanning. It has since become one of the most popular types of two-dimensional barcodes.
Unlike the older one-dimensional barcode that was designed to be mechanically scanned by a narrow beam of light to extract data, the QR code is detected as a 2-dimensional digital image by a semiconductor image sensor and is then digitally analyzed by a programmed processor. The processor locates the three distinctive squares at the corners of the image, and uses a smaller square near the fourth corner to normalize the image for size, orientation, and angle of viewing. The small dots are then converted to binary numbers and validity checked with an error-correcting code.
You can create your own QR Codes by clicking one site here.
At my local Starbuck's, you can wait for your latte and scan listings of houses for sale in Santa Rosa. You hold up your phone, point and click. A smart broker has QR Codes displayed at the window just past the pickup counter. Quite brilliant. No wasted time for busy people on the go.
I'm waiting for the day when you can click on a QR Code and get transported to someplace sunny and warm. Beam me up, Scotty.
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