Wii modding and online updating
The Wii Menu (known internally as the System Menu) is the name of the user interface for the Wii game console, and it is the first thing to be seen when the system boots up.
Similar to many other video game consoles, the Wii is not only about games.
Splatoon is set to wind down on content updates in January 2016 and some of the final weapons are starting be revealed.
Nintendo have pledged that Splatfest events and balancing patches will continue to keep the game running on Wii U, it is still unclear just how much new content will be added before it stops.
IOSes are referred to by their number, which can theoretically be between 0 and 254, although many numbers are skipped, presumably being development versions that were never completed. The only time an IOS isn't running is when the Wii enters Game Cube backward compatibility mode, during which the Wii runs a variant of IOS specifically for Game Cube games, MIOS.
When a new update becomes available, Nintendo sends a message to connected systems notifying them of the available update.