Productivity Sauce

The latest version of the Raspbian Linux distro for Raspberry Pi contains a graphical tool for configuring and managing wireless connections, but you can easily set up a wireless connection to a WPA-protected Wi-Fi network without booting into a graphical desktop environment. Assuming that you are using a wireless adapter supported by Raspbian, run the iwconfig command to find out the correct wireless interface (in most cases, it's wlan0). Create then a backup copy of the /etc/network/interfaces network configuration file using the following command:

sudo cp /etc/network/interfaces /etc/network/interfaces.old

Open the file in the nano editor:

sudo nano /etc/network/interfaces

Locate the default configuration of the wlan0 interface which should look something like this:

allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp

Replace it with the following profile:

auto wlan0
iface wlan0 inet dhcp
wpa-ssid [ESSID]
wpa-psk [PASSPHRASE]

Reboot your Raspberry Pi, and it should automatically connect to the configured network.