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 ...

Javascript reduce method parameters The reduce method accepts two arguments: a reducer function for the array that is used as a callback, and an optional initialValue argument.

Learn JavaScript's Array Reduce method in 100 seconds. Take many things and reduce them down to one thing.