The original gray Game Boy was first released in Japan on April 21, 1989. Based on a Z80 processor, it has a black and green reflective LCD screen, an eight-way directional pad, two action buttons (A and B), and Start and Select buttons with the controls being identical to the NES controller. It plays games from ROM-based media contained in cartridges (sometimes called carts or Game Paks). Its graphics are 8-bit (similar to the NES).

The game that pushed the Game Boy 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 children alike were buying Game Boys in order to play Tetris. Releasing Tetris on the Game Boy was selected as #4 on GameSpy's "25 Smartest Moments in Gaming".

The original Game Boy was one of the first cartridge-based systems that supported networking: two devices with a Game Link Cable, or up to four with the Four Player Adapter.

In 1995, the "Play it Loud" version of the original Game Boy was released in six different colors; black, red, yellow, green, blue, white and clear as well as additional sports-themed editions.

Game Boy Pocket

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