The delta of binary call options is the first derivative of the option price after a change in the strike price. Thus, the delta of binary call options indicates the slope of the binary call option price profile.
It represents an immediate equivalent position in the underlying asset, regardless of whether it is a binary call option, a conventional put option, or an exotic option.
The delta of at-the-money options tends to infinity when the time to expiration approaches zero. Those familiar with binary options greeks know that the gamma is the first derivative of the delta and that the gamma of a conventional option is always positive.
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