This system is widely used in horse racing, but also became popular in roulette. The Parlay system is based on the premise that when a bet is successful, the next bet will be the value of your last bet plus gains - a Let It Ride System.
A system of betting for cool and cold players looking to reach a bet of substantial value through the accumulation of winning bets and thus win win big in final bet.
The advantage of this system is that it is based, above all, in the accumulated profit at the roulette, and not in the budget of the player to make that bet of significant value - thereby protecting better the player's budget than in other systems like the Martingale roulette that is based heavily on the budget size of the player.
Before starting to play is important to define how many consecutive bets you willing to do until you return to the original bet. Many players bet three consecutive wins and then return to the initial bet and repeat the bet until a victory - with a win the the parlay parlay begins. This system is often used in conjunction with other roulette systems:
Chameleon Strategy - you identify a great player performance on the roulette and you replicate their number bets but using the parlay system;
Strategy Guerrilla or Hit and Run - Star a bet a given sequence or series of numbers that the player considers to be particularly appealing eg: consecutive twelve numbers of 1 to 18. If you win you take the profit and leave the table without even blinking twice!
With the system parlay and if you're lucky you can make real money. In a sequence losing only lose one drive loss. It is a system where you do not lose much, but you risk a lot to gain.
Below, the illusionist David Blaine uses this system to "make magic." Risk 5 times in a bet with a probability of 48% and bet in a color in a almost random fashion.