You can scan a QR code using the camera on your smartphone, tablet, or computer — however, you may need to download an app.

QR codes are a type of barcode, or scannable pattern, that contain various forms of data, like website links, account information, and phone numbers.

In New South Wales, Australia, where Mr. Wilson lives, QR codes for tracking pandemic behavior are posted at restaurants and retail stores. However, if you print the 'File that describes the QR code ...