Monads are easy to understand: A monad is exactly anything that satisfies the three monad laws.
If you have worked with mathematical groups and have seen how mathematicians can look at very disparate things with their group-goggles and find similarities, you will appreciate monads.
The y combinator is a nice parlour trick (if you define it in lambda calculus without using any other recursion primitives), and research vehicle. But I did not apply it once, yet. And I've tried.
If you want to get combinatorial logic (including the y combinator), read "To Mock a Mockingbird". And do all the puzzles, of course. Actually you should read it, whether you want to learn anything about combinatorial logic or not. It is such a good book.
If you have worked with mathematical groups and have seen how mathematicians can look at very disparate things with their group-goggles and find similarities, you will appreciate monads.
The y combinator is a nice parlour trick (if you define it in lambda calculus without using any other recursion primitives), and research vehicle. But I did not apply it once, yet. And I've tried.
If you want to get combinatorial logic (including the y combinator), read "To Mock a Mockingbird". And do all the puzzles, of course. Actually you should read it, whether you want to learn anything about combinatorial logic or not. It is such a good book.