JAMMA=Japanese Arcade Machine Manufacturers Association
An old group trying to set standards for board pinouts (at arcade machines).
This was designed to make board changes easy, just take out the old
game and plug in the new. Unfortunately games have evolved, and the Jamma
standard is no longer up to the job as it can`t handle more than 4 buttons or
two players. Also replacing a board from a different manufacturer meant
readjusting the picture on the monitor as it would not be centred in the same
position.