A promise is a class whose constructor accepts an executor that accepts two arguments that are also functions. The first is defined as resolve, and the second is defined as reject. A promise is a class whose constructor accepts an executor that accepts two arguments that are also functions. When a promise is executed, reject indicates failure, and the value is passed to the then callback. Promise returns the then method, which takes two arguments, one for a successful callback and one for a failed callback. The then method follows the resolve and reject execution (in publish subscriber mode). 4. Promise supports chaining calls, and then returns a New Promise