In this friendly introduction to functional programming with JavaScript, you'll learn what Functional Programming (FP) is and how it differs from other programming styles (such as OO and imperative). You'll practice the key idea of doing everything with pure functions, learning to use higher-order functions and recursion to replace the iterative loops we're used to writing with for and while. You'll more to advanced techniques like closures, currying, and function composition and learn why immutable data is essential for functional programming. This course and others like it are available as part of our Frontend Masters video subscription.