The Sega Master System (SMS) was originally a remodeled export version of the Sega Mark III, the third iteration of the SG-1000 series of consoles, which was released in Japan in 1985 and featured enhanced graphical capabilities over its predecessors. The Master System launched in North America in 1986, followed by Europe in 1987, and Brazil in 1989.
The original Master System models use both cartridges and a credit card-sized format known as Sega Cards. Accessories for the consoles include a light gun and 3D glasses that work with a range of specially designed games. The later Master System II redesign removed the card slot, turning it into a strictly cartridge-only system and is incompatible with the 3D glasses.