Files I always add to a Raspberry Pi Raspbian Micro SD card before first boot (SSH and WiFi settings)
Both files should be placed in the root of the 'boot' partition after burning a new Raspbian image to a Micro SD card, before inserting it in to a Raspberry Pi for the first boot.
ssh
This 'ssh' file is a blank file, with no file extension. It enables SSH on the Raspberry Pi.
wpa_supplicant.conf
This is template for the wpa_supplicant.conf file.
You should edit the file to have your 'SSID
' (WiFi network name) and 'PSK
' (pre-shared key/password). scan_ssid
allows it to find "hidden" wifi networks, ones which aren't actively broadcasting their SSID, despite being an active WiFi network. These settings do assume you are using a secured WiFi network with a password (eg: secured with WPA2 or may also be called WPA2-PSK in your router)
If you are not in the United Kingdom you should also change the country from GB
to your relevant country code.
Further detailed information about
wpa_supplicant.conf
can be found on the official Raspberry Pi Documentation