This tag should only be used if the question is about the Wii operating system or hardware, or a game feature truly unique to the Wii.
The Wii is the fifth console by Nintendo, released on November 19, 2006, and primarily competes with Microsoft's Xbox 360 and Sony's PlayStation 3.
A distinguishing feature of the console is its wireless controller, the Wii Remote, which can be used as a handheld pointing device and detects movement in three dimensions.
There is an add on Wii Motion Plus which allows more accurate motion capture and increasing numbers of games are making use of it's features.
Another unique feature of the Wii is being able to play all Gamecube games, and being able to play select games from all previous Nintendo and certain non-Nintendo consoles trough it's Virtual Console Service.