What Is a Monad?

A monad is a type equipped with a way to wrap a plain value and a way to chain functions that each take a plain value and return a wrapped one. This chaining operation threads the wrapped context through a sequence of steps without manual unwrapping. Optionals, lists, and async results are commonly modeled as monads to compose computations that carry extra context.

Why it matters

Monads give a uniform pattern for sequencing computations that involve effects like optionality, failure, or async, hiding the plumbing of passing context along. Recognizing the pattern makes such chained operations cleaner and less error-prone.

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