Explain why

[alper]

A monad is an object with of and chain functions.

An object that has extract and extend functions.

Explain why this is. Like this it doesn't explain jargon, it just adds more.

[CrossEye]

Feel free to have a go. There's a cottage industry of Monad tutorials, and they all seem to fail when they start making analogies.

I'd love to see one that didn't. (Beside's Tom Harding's but that takes going through fifteen other tutorials first.)