Functional programming gets a bad wrap about being too hard for mere mortals to comprehend. This is nonsense. The concepts are actually quite simple to grasp.
The jargon is the hardest part. A lot of that vocabulary comes from a specialized field of mathematical study called category theory (with a liberal sprinkling of type theory and abstract algebra). This sounds a lot scarier than it is. You can do this!
All examples using ES6 syntax. wrap (foo) => bar means:
function wrap (foo) {