Last time, we saw how to change existing items in an array using their index, like colors[1] = "yellow";.

But what if you want to add a new item to the array without replacing an existing one.

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How might you add to the collection?

JavaScript arrays have a special built-in function (called a method) just for this: .push().

This method adds the specified item to the very end of the array. The array grows longer.

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With me so far?

Here's how you use it: arrayName.push(newItem).

If we have let tasks = ["review code"];, and we run tasks.push("write tests"), the array changes.

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How long do you think the tasks array will be after this operation?

After running that command, the tasks array becomes ["review code", "write tests"]. The new item "write tests" is added to the end!

You can push items of any data type (strings, numbers, booleans) to an array.