The original Game Boy was released on April 21, 1989 in Japan
and in August 1989 in the United States. Based around a Z80
processor, it had a black and green reflective LCD screen, an
eight-way directional pad, and two action buttons. It played
games from ROM-based media contained in small plastic detachable
units called cartridges (sometimes abbreviated as carts). The
game that really pushed it into the upper reaches of success was
Tetris. Tetris was widely popular, and on the handheld format
could be played anywhere. It came packaged with the Game Boy,
and broadened its reach; adults and kids alike were buying Game
Boys in order to play Tetris anywhere. It is considered to be a
killer game for the Game Boy that made it hugely popular.
Releasing Tetris on the Game Boy was selected as #4: Tetris
Makes Game Boy a Must-Have on GameSpy's 25 Smartest Moments in
Gaming. The original Game Boy was the first cartridge-based
system that supported more than four players at one time (via
the link port). In fact, it has