Comment by ndriscoll

"The meme" literally comes from a book that was offering it as an intuitive explanation of a long definition, assuming you know what a monoid is. All the laws and stuff boil down to "if you generalize the idea of a monoid a little bit, and if you have some functor+flatten+wrap forming a monoid, we call that a monad." If you don't know what that stuff means then obviously it's not for you, but if you do, then it's actually a concise way to say "what it is," which is basically just that flatten is associative and wrap is neutral.