A Zero-sum Game

In game theory and economic theory, a zero-sum game is a situation in which each participant’s gain (or loss) of utility is exactly balanced by the losses (or gains) of the utility of the other participants. If the total gains of the participants are added up and the total losses are subtracted, they will sum to zero. Thus cutting a cake, where taking a larger piece reduces the amount of cake available for others, is a zero-sum game if all participants value each unit of cake equally

In contrast, non-zero-sum describes a situation in which the interacting parties’ aggregate gains and losses can be less than or more than zero. A zero-sum game is also called a strictly competitive game while non-zero-sum games can be either competitive or non-competitive

Binary options are exactly that (with the exception of the brokers commission), so for every gain you make someone lost and vise versa.

Saying that, you must know that usually odds are highly biased in favor of the brokers. Competition from so many brokers trying to win your favor has improved the odds lately, but for a common payoff ratio of 70%, including a 15% rebate feature, a trader must still win 55% of the time to break even.

Advantages and Disadvantages of binary trading