Creating Arrays of Arrays (Nested Arrays) in JavaScript: Common Pitfalls and Best Practices

Creating Arrays of Arrays (Nested Arrays) in JavaScript: Common Pitfalls and Best Practices

Working with arrays of arrays—often referred to as "nested arrays" or "2D arrays"—is a common requirement in JavaScript when dealing with matrices, grids, or tabular data. However, the way we initialize these structures can introduce subtle bugs if we’re not careful! In this post, we’ll walk through the right and wrong ways to create arrays of arrays in JavaScript, explain why certain pitfalls occur, and show you best practices for robust code. …