Last time, we saw that repeating tasks is tedious. JavaScript gives us tools for this, and the first one we'll learn is a type of for loop.

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Ready to see how it works?

The for...of loop is perfect for repeating an action for each item in a collection, like an array.

It's like saying, "For each student in my class list, hand them a book."

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Make sense?

If you have an array like let myItems = ["pen", "book"];, a for...of loop will run two times—once for "pen" and once for "book".

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If an array has 3 items, how many times does the loop run?

Before we see the loop structure, let's learn about a new keyword: const.

You already know let creates a variable that can be changed later. const creates a variable that cannot be reassigned once it's set - it's constant.

In loops, we use const for the loop variable because it gets a new value automatically in each iteration, but within each single loop cycle, that value shouldn't change.