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A Game of Concentration is an early Atari 2600 game from 1978, based on Concentration. Cards are selected from either a 4x4 or 5x6 grid, using the 2600's numeric keypad controllers. If the images match, the player scores either one or two points, depending on the difficulty switches, and gets another turn. There are also wild cards that match anything.
A Game of Concentration provides examples of: