The Wii U is an eighth-generation console released by Nintendo in 2012. It is the first console by Nintendo to output to high-definition (HD) resolutions, such as 720p and 1080p. It includes a tablet-like controller, known as the Wii U GamePad, to provide certain additional gameplay. Notably, it can play all Wii games, as well as supporting the Wii Remote controllers for native Wii U games.
Cemu is the first Wii U emulator released, in October 2015. Cemu is current under active development, and making significant progress. It is capable of outputting Mario Kart 8 at around 60 FPS, and Super Mario Maker at 60 FPS. Synchronized sound is only partially supported in a few games, and visual accuracy for most games is poor. It doesn't yet support Virtual Console emulation.
Decaf is another Wii U emulator under active development.