Haskell monads have been described as "programmable semicolons" because they specify ways to interpret "do" blocks.
In some sense they are a little bit similar to Python classes. A Python class is a block of code, which runs in a normal Python way, and then the variables put in scope by that code are passed to a metaclass constructor which creates some kind of object based on them. Monads are nothing like that, but they are similar in that user code is interleaved with framework code to produce an effect similar to a DSL. Monads run one statement at a time, interleaving one statement execution with one monad join operation.
In some sense they are a little bit similar to Python classes. A Python class is a block of code, which runs in a normal Python way, and then the variables put in scope by that code are passed to a metaclass constructor which creates some kind of object based on them. Monads are nothing like that, but they are similar in that user code is interleaved with framework code to produce an effect similar to a DSL. Monads run one statement at a time, interleaving one statement execution with one monad join operation.