Looping Over Arrays: for vs. for-in vs. .forEach() vs. for-of

In JavaScript, there are multiple ways to loop over arrays, each with its own use case and performance characteristics. Understanding the differences between the for loop, for-in loop, .forEach() method, and for-of loop is crucial to writing clean, efficient, and readable code.

Let’s explore these looping mechanisms, highlighting their differences, use cases, and examples.

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1. for Loop

The classic for loop is the most flexible and widely used looping construct. It gives you full control over the loop's initialization, condition, and iteration. It allows you to loop over an array by directly accessing elements via their indices.

Syntax:

for (let i = 0; i < array.length; i++) {
  console.log(array[i]);
}

Key Features:

• Fast and efficient: It provides maximum control and is typically the most performant option.
• Access elements by index: You have access to the current index (i), which can be useful for situations where you need both the index and the element.
• Can control loop behavior: You can break, continue, or modify the…