Betting Strategy

The Martingale comes from the world of casino gambling, and in particular the game of roulette where the gambler must decide whether the ball will land on either a red or a black number after each spin. The basic Martingale strategy is to double the stake size after each losing wager, and return to the starting stake after every win.
For example if a player starts at $1 and loses four bets in a row, winning on the fifth, he will have lost $1+$2+$4+$8 = $15 on the four losing bets and won $16 on the fifth bet. The losses were covered and he had a profit of $1. The problem is having enough money to cover lose of several bets in a row.