A Wi-Fi QR code contains a text payload describing the network. The original note used the following format and a simple example:
WIFI:S:<SSID>;T:<WPA|WEP|>;P:<password>;;
Ex:
WIFI:S:ExampleNetwork;T:WPA;P:hello;;S names the SSID, T identifies the authentication type, and P carries the password. The angle-bracketed values describe fields; they are not literal values to include in an actual network payload.
The example SSID has been replaced with a generic name. Special characters and different authentication modes need their own handling; this short pattern is not a complete escaping specification.
QiFi was the generator linked by the original note. A QR code containing the network password should be shared with the same care as the password itself.