The Nintendo Game Link Cable is an accessory for the Game Boy line of handheld video game systems, allowing players to connect Game Boys of all types for multiplayer gaming. Depending on the games, a Game Link Cable can be used to link two games of the same title, like Tetris, or two compatible games like Pokémon Red and Blue, and co-op Super Mario Land. Games can be linked for head-to-head competition, cooperative play, trading items, unlocking hidden features, etc.
The first generation Game Link Cable (model DMG-04) was released alongside the original Game Boy and has "large" connectors on both ends. It can only be used to link two original Game Boys to play Game Link-compatible games, usually denoted by a "Game Link" logo (often read as "Game Boy Video Link") on the packaging and cartridge.
A select few Game Boy games, such as F-1 Race, supported multiplayer modes for up to four players, although this requires the use of up to three additional Game Link cables and the Game Boy Four Player Adapter (model DMG-07).