JavaScript’s arrays can hold heterogeneous ... are said to be “pure functions.” We can use forEach in this way, but the Array.map() function is specifically designed for this purpose.

Some of these use cases overlap with the forEach , map, and filter array methods. So you should know to pick the situations that can be solved optimally using the reduce method.

Arrays are wonderful and a very particular type in JavaScript. There are many useful built-in properties and methods that will help you resolve any task which involves this kind of type.