[m_arnold]

If you want to know:

A monoid is just a collection of things that can be associatively "added". Think addition with integers, or append with lists.

Members of the dreaded monad can be sequenced, or composed, while taking into account their context. For instance: if I want to get a value from stdin, then use that value safely; or make a network request and then use the result safely; or run a function that can fail, and use it or short-circuit as needed.