It’s used for scanning the QR code displayed on the computer (or phone). The QR code contains: - the monetary amount, - parts of the recipient’s account numb

It’s used for scanning the QR code displayed on the computer (or phone). The QR code contains: - the monetary amount, - parts of the recipient’s account number (both helps thwart MITM attacks) - and a random challenge (which helps prevent replay attacks.) That’s for the wireless model. Wired CAP devices don’t have a camera since they can use USB.