The N12 roulette strategy is a betting system where you bet on any 12 numbers on the roulette board. The strategy involves a specific bankroll and betting progression to make money. You start with a bankroll of $576 and a starting bet of $12. If you lose, you can afford to lose twice before needing to adjust your bet. After two losses, you double up your bet, and if you lose again, you add a unit to each of the 12 numbers you are betting on. This strategy is not a Martingale system, as you do not keep doubling up indefinitely.