 Developed under the name "Project Mercury" and designed based on the Master System's hardware, the Game Gear is a handheld game console. It was first released in Japan on October 6, 1990, in North America and Europe in 1991, and in Australia in 1992. Originally retailing at JP ¥ 19,800 in Japan, US $ 149.99 in North America, and GB £ 99.99 in Europe, the Game Gear was designed to compete with the Game Boy, which Nintendo had released in 1989. Despite the similarities the Game Gear shared with the Master System, the games of the latter were not directly playable on the handheld, and were only able to be played on the handheld by the use of an accessory called the Master System Converter. A large part of the Game Gear's game library consists of Master System ports. Because of the landscape orientation of the Game Gear's screen and the similarities in hardware between the handheld console and the Master System, it was easy for developers to port Master System games to the handheld.
