The NES Test Cart, also known as the Official Nintendo Seal of Quality Test Program, was a diagnostic tool developed by Nintendo for testing and certifying NES games. It was not a game itself, but rather a cartridge that contained a suite of tests to ensure that games met Nintendo's quality standards and would function properly on the NES hardware. The tests included checks for graphics, sound, input controls, memory, and other technical aspects. The NES Test Cart was only available to licensed game developers and was not sold commercially.
