>>Each monad, or computation type<<

That seems to be saying that monad and "computation type" are synonyms. But surely this is just bad writing? A monad is a CT, but a CT doesn't have to be a monad? And what is the point of adding the verbiage of "computation type" in what will be a massive sentence anyway?

>>provides means, subject to Monad Laws,<<

I think it's expected that monads will follow monad laws and provide means to do something..

>>> to (a) create a description of computation action that will produce (a.k.a. "return") a given Haskell value<<<

This is just bizarre. The monad can create a description of a computation action? What does that mean - a comment is a description - does it mean that? And does it mean the description will do the returning or that the computation action will? And why say "means" instead of something more specific and meaningful (for example, I'm guessing the means might be a function..)