I think for newbies there are two separate aspects to explain: first an intro to algebraic structures perhaps using groups as an example, then monads in particular.
It’s important to emphasize that algebraic structures are abstractions or “interfaces” that let you reason with a small set of axioms, like proving stuff about all groups and writing functions polymorphic for all monads.
With monads in particular I think the pure/map/join presentation is great. First explain taking “a” to “m a” and “a -> b” to “m a -> m b” and then “m (m a)” to “m a”. The examples of IO, Maybe, and [a] are great.
You can also mention how JavaScript promises don’t work as monads because they have an implicit join semantics as a practical compromise.
It’s important to emphasize that algebraic structures are abstractions or “interfaces” that let you reason with a small set of axioms, like proving stuff about all groups and writing functions polymorphic for all monads.
With monads in particular I think the pure/map/join presentation is great. First explain taking “a” to “m a” and “a -> b” to “m a -> m b” and then “m (m a)” to “m a”. The examples of IO, Maybe, and [a] are great.
You can also mention how JavaScript promises don’t work as monads because they have an implicit join semantics as a practical compromise.