4.Encrypt Your Wifi Password - NaimFuad/RaspberryPiWithOpenCV GitHub Wiki
Your Wi-Fi password that you register will be saved as a readable text. It is a good idea to encrypt your password from others.
You can view your registered Wi-Fi password on wpa_supplicant.conf file. On Raspberry Pi navigate to this directory etc/wpa_supplicant and you can open the wpa_supplicant.conf by Right Click > Open With > Custom Command Line > enter ‘sudo leafpad’ (make sure you installed leafpad note editor)
You can also view it in terminal:
$ sudo nano /etc/wpa_supplicant/wpa_supplicant.conf
Below is an example of registered network name with password that are readable
To encrypt, open terminal and run the following command
$ wpa_passphrase [SSID NAME] [PASSWORD]
Copy the output from the terminal to your wpa_supplicant.conf file.
Reboot your Raspberry Pi
$ sudo reboot now