The Sega Master System is a third-generation 8-bit home video game console manufactured by Sega. It 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 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.