What is monad in functional programming?
Can you show me example of implementation of monad in Haskell?
A monad is a type with a function that creates that type, and a function that produces a new computation for values of that type.
Here is an example implementation of a monad `m` in Haskell:
```haskell
-- type constructor for the monad
data m a = ...
-- embed the input value in the monad `m`
return :: a -> m a
-- bind function that returns a computation to combine `a` and `m b` into `m b`
(>>=) :: m a -> (a -> m b) -> m b
```
Why actually should I care about monads?
You might care about monads if you are writing functional code and need to deal with computations that have side effects, or if you want to abstract away certain details and make your code easier to reason about. Here are some specific benefits of using monads:

1. Handling side effects: Monads provide a way to handle side effects (such as I/O or state) in a controlled and composable way. This can make your code more predictable, easier to test, and easier to maintain.

2. Structuring code: Monads add structure to your code, making it easier to understand and reason about. They provide a way to describe the flow of data through a series of computations, making it easier to see how each step depends on the others.

3. Simplifying error handling: Monads provide a way to handle errors and exceptional conditions in a controlled and composable way. This can make your code more robust and easier to maintain, as it separates error handling logic from the rest of your code.

4. Improving code reuse: Monads make it easier to reuse code, as they provide a way to abstract away certain details and make functions more general. This can make your code more modular and flexible, making it easier to build and maintain large systems.

It's important to note that monads are not always necessary, and their use can sometimes add complexity to your code. Whether or not to use monads depends on the specific needs of your project and your personal preferences. However, for functional programming enthusiasts, understanding monads can be an important tool in your functional programming toolbox.