Binary option 二元期权
A binary option is a financial option in which the payoff is either some fixed monetary amount or nothing at all. While binary options are used in a theoretical framework as the building block for asset pricing and financial derivatives (a binary option maps to the cumulative distribution function of the risk-neutral distribution ), they have been exploited by fraudulent operations as many binary option outlets (outside regulated markets) have been shown to be scams. The two main types of binary options are the cash-or-nothing binary option and the asset-or-nothing binary option. The cash-or-nothing binary option pays some fixed amount of cash if the option expires in-the-money while the asset-or-nothing pays the value of the underlying security. They are also called all-or-nothing options, digital options (more common in forex/interest rate markets), and fixed return options (FROs) (on the American Stock Exchange).