The Mario Kart Channel is a channel that launched at the same time of Mario Kart Wii. This channel allows players from around the world to play each other through Nintendo's wifi service, WiiConnect24.
When you are in the Mario Kart Channel you have a choice of three things to do: worldwide, regional and friends. Worldwide and regional match up players of similar rankings. The option to play friends lets
you play anyone that is registered on your friends list. When playing with friends you are able to send simple text messages to one another.
The Channel also hosts competitions made by Nintendo.
It is optional to install the Mario Kart Channel to your Wii dashboard. You can view the current rankings and send or receive time trials (ghosts). The channel can run independently from the game.