The ins and outs of JavaScript reducer — a simple, yet powerful array method

JavaScript’s reduce is one of the most useful array methods that should be in a developer’s arsenal. Introduced in ES5, it’s somewhat similar to for…each and map methods that are used with arrays, but improves on their performance and simplicity in specific situations. The reduce method executes a callback function that we provide on each element stored in an array and outputs the final value the operation generates. It’s a cleaner way of iterating over and proces