JavaScript Iterators
JavaScript Iterators are objects that implement the Iterator protocol, providing a standardized way to traverse data structures like arrays, strings, maps, and sets. They define a `next()` method that returns an object with `value` and `done` properties, enabling sequential access to elements. This concept underpins features like `for...of` loops and is foundational to iterable objects in JavaScript.
Developers should learn JavaScript Iterators to work efficiently with collections and custom data structures, as they enable lazy evaluation, memory-efficient processing of large datasets, and integration with modern JavaScript features like generators and async iteration. They are essential for implementing custom iteration logic, such as in data pipelines or when creating library APIs that need to be iterable.