Monads

How are monads different than side effects?

Haskell Monads are actually a triplet of an abstract data type, and the functions bind and return. Each monad has its own specific bind function and its own specific return function. You can use monads as a way of abstracting "common computations". Monads can be also used to implement a sort of "container" for data. As for side effects in monads, you're probably thinking about the IO monad which can be thought of as a container that manages side effects to the real world.