Consider this a crash course in working with QR codes on Linux.
A QR code is an image that represents a URL. It can be quickly and conveniently scanned by the camera on a mobile device to open the link, rather than having to type it in manually.
The following packages will need to be installed.
sudo apt-get install qrencode zbarimg feh
Creating a QR Code
qrencode -o "./cyberfella.png" "https://www.cyberfella.co.uk"
Viewing a QR Code
Reading a QR Code