MiniDVD

MiniDVD (Mini DVD or miniDVD) is a DVD disc which is 8 centimetres (3.15 in) in diameter. Most MiniDVDs hold 1.4 GB of data, but there are variants that hold up to 5.2 GB.

The 8 cm optical disc format was originally used for music CD singles, hence the commonly used names CD single and miniCD. Similarly, the manufactured 8 cm DVDs were originally used for music videos and as such became known as DVD single.

MiniDVD is known also as "3 inch DVD", referring to its approximate diameter in inches.

A MiniDVD can be played back in most Blu-ray and DVD players that are tray loaded. The trays on players and DVD drives have an inner ring where the 8 cm disc is centered for loading in the player. Most slot loading players cannot use this format; there are exceptions, however, such as the Xbox 360, PlayStation 3, and the Wii. However, the Wii U does not.

Recordable 8 cm discs are commonly used in DVD-based camcorders. The most common MiniDVDs hold 1.4 GB of data, but there are variants that can offer up to 5.2 GB of storage space.

Nintendo used a disc-based format for their GameCube system, which is a variant of an 8 cm DVD. This format is also supported by the Wii.

...
Wikipedia