In this example i will explain high order function

high_order_function.js

const hocFn = function() {
  return function() {
    return 5;
  }
}
hocFn() // will return function
hocFn()() // will return 5
// hocFn return function so it is HOC

const fn = function(x) {
  return x*2;
}

const hocFn2 = function(fn) {
  return fn(5);
}

hocFn2(fn); // will return 10
// hocFn2 accept function as argument it is an HOC