Mastering Array Flattening in JavaScript: From Nested Chaos to Clean Lists

Imagine you're building a shopping cart app. Users add items like ["apple", "banana", ["orange", ["grape", "kiwi"]]] . Suddenly, your loops break because of those sneaky nested arrays. Frustrating, right? Array flattening turns this mess into a simple ["apple", "banana", "orange", "grape", "kiwi"] . In this blog, we'll demystify nested arrays, explore why flattening matters, break down approaches step-by-step, and tackle real interview scenarios—including a custom polyfill you can steal (or impr