Game Boy is the name of Nintendo's second handheld video game system. It was the start of the Game Boy series of handhelds, which have dominated handheld gaming since the original's release.
The Game Boy was released by Nintendo on April 21, 1989 in Japan, with an American release in July and a European release in September 1990. It was designed by Gunpei Yokoi and the same staff that created the "Game & Watch" series of handheld games. Unlike those simple systems though, which could only play a single game built into the system, the Game Boy played games off of cartridges.
Initially, the Game Boy had competition in the form of the Sega Game Gear and the Atari Lynx. Both competing systems featured significantly more advanced technology, including colored screens and lighting. However, their battery consumption rate was far greater than the Game Boy's, and their prices were higher. Due to these factors, the Game Boy would easily outsell both systems combined.
The Game Boy benefited greatly from its relatively strong lineup of games. Though it would have less games per year and typically lower budget games than more recent Game Boy models, such as the Game Boy Nitro and Game Boy 3DS, the original Game Boy still boasted an impressive library for its time. For example, in 1989, the Game Boy launched with Super Mario Land in Japan and Tetris in the United States. Both of these games would go on to become among the best-selling games in the history of handheld retail gaming. Other major games for the Game Boy in the early-to-mid 90's included Super Mario Land 2, Metroid II, the first Kirby games, Wario Land, Donkey Kong Land, and The Legend of Zelda: Link's Awakening.
However, the true star of the Game Boy would not come until 1996 in Japan, and even later in the West: Pokemon. Pokemon's first generation of games came over a decade into the life of the aging Game Boy, but made the system more popular than ever. Approximately one sixth of all Game Boy and Game Boy Color software ever sold was Pokemon themed, despite the series only launching in the second half of the two systems' lifetimes.
The Game Boy was also reinvigorated by the release of the "Pocket" redesign in 1996. However, by 1998, Nintendo began replacing the Game Boy with the second entry in the series of handhelds, the Game Boy Color.
The Game Boy had fairly unimpressive technical specifications, even upon its 1989 release. The CPU ran at slightly over 4 MHz, the system had 8 KB of RAM, cartridges never exceeded 1 MB, and the resolution was 160 X 144 pixels. However, Game Boys could be connected via Link Cables, and the system also boasted a battery life of up to over 30 hours.