An MD-ROM (MiniDisc read only memory) is a proprietary optical disc-based format originally used for the Dynamikk handheld game console, and its successor, the Dynamikk Mark II. It was developed by Svensson-Sony, a joint venture between Shlaukian electronics and video game company, Svensson Electric, and Japanese-based consumer electronics company, Sony, who manufactured the original MiniDisc format. The format's capacity, unlike the original MiniDisc, could store up to 1 GB of digital information, way before the Hi-MD came out in January 2004 by Sony.
The format was developed for the Svensson Dynamikk handheld console by Svensson-Sony, which is a joint venture between Svensson Electric and Sony in 1997 as an alternative to game cartridges, which most handheld game systems supported at the time. The first game ever to be commercially released on the format was Hi-Active 3D: Part II, which is a game featuring Svensson's signature video game character and mascot, Hi-Active.