Reviews For Payless ShoeSource Customer Service (5) bad manager at 567...warrenton, or Over heard a store manager at 567 repremand an employee for not showing me a shoe... really not needed.
Haskell is most likely quite different from any language you've ever used before. Compared to the usual set of concepts in a programmer's mental toolbox, functional programming offers us a profoundly different way to think about software. In Haskell, we de-emphasise code that modifies data.
Not quite like multithreading... You use a callback anytime you need to wait on something external to your primary JS code. In a browser this is used a ton for AJAX, and in node.js it's used for every single thing that calls out to the system (file access, networks access, database requests, etc).