You can manage all your wireless communication here. Wireless connections can include Wi-Fi, 3G, 4G, Bluetooth, etc.
There is a switch in this section to nuke all your wireless connections. Turning it on will stop all possible wireless communication with your machine.
Besides that, you may switch off individual wireless devices. The only device that I possess is Wi-Fi. Bluetooth, 3G, 4G, etc. also usually shows up here.