Think of a monad as a programmable semi-colon (who coined that term again?). Then you can build a monad for error-handling, backtracking, continuations, or what

Think of a monad as a programmable semi-colon (who coined that term again?). Then you can build a monad for error-handling, backtracking, continuations, or whatever control-flow primitive you need. You probably wouldn't use the IO (to sequence IO operations) or State (to maintain state) monads in Python, though.