Wi-Fi is a facility allowing computers, smartphones, or other devices to connect to the Internet or communicate with one another wirelessly within a particular area.
Mario Kart Wii uses Wi-Fi connection to allow taking part in races with friends and/or strangers, rather than bots.
Wi-Fi is used to establish a connection between multiple people on a server.
Mario Kart Games With Online WiFi[]
*Mario Kart Wii online has been disconnected, however there are still ways to play online