You see QR codes just about everywhere these days. The square barcodes show up everywhere: real estate listings, TV ads and social media posts touting what look like great deals on must-have items.

QR codes have become an essential part of modern life, from scanning restaurant menus and making digital payments to sharing contact details and promoting businesses. These black-and-white squares are ...

First invented for use in industrial applications in Japan in the early 1990s, QR codes were being widely used by consumers when smartphones with QR readers became more prevalent in the 2000s. After ...