Functions are self-contained routines that can be “called” elsewhere within your JavaScript code. Along with loops and conditionals, functions are an essential means of organizing software.

If you write JavaScript, you have probably used higher-order functions and not even noticed. If you have ever replaced a for loop with an array method, you’ve used higher-order functions.

Most websites are programmed using JavaScript, which is essential for more advanced or complex operations and functions. JavaScript can also be used to program, and there are a lot of resources ...