QR Code

A QR code (Quick Response) is a 2D barcode that encodes data - usually a URL. Point the phone camera at it and the OS recognises it and offers to open the link.

QR's strength is broad compatibility: almost any camera-equipped phone can scan one, even older models without NFC support. The trade-off is a few more steps for the user and real estate taken up by the design. That's why combining both technologies is common - see QR vs NFC.