The `.reverse()` method is used to reverse the order of elements in an array. It mutates the original array, meaning it changes the array in place and does not create a new array.

Here is an example of using `.reverse()`:

```javascript
const array1 = ['one', 'two', 'three'];
array1.reverse();

console.log(array1); // ['three', 'two', 'one']
```

Note that `.reverse()` mutates the original array. If you want to reverse the order of the elements in an array without mutating the original array, you can clone the array first, then reverse the clone.

```javascript
const array1 = ['one', 'two', 'three'];
const reversed = [...array1].reverse();

console.log(array1); // ['one', 'two', 'three']
console.log(reversed); // ['three', 'two', 'one']
```

As you can see, the original array is not mutated, because we cloned it first using the spread operator.

## Code Challenge

There are some methods from arrays that works with strings too, but the `reverse()` method is not one of them.

Use what you learned so far to reverse the string "Hello World".