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The `reverse()` method in JavaScript **reverses the order of the array's elements**,
meaning the first becomes the last, and the last becomes the first.

## Example:

```javascript
const arr = [1, 2, 3, 4];
arr.reverse();

console.log(arr); // [4, 3, 2, 1]
```

- Elements are rearranged **in place** (in the original array).
- The method **mutates** the array.
- Returns **the same modified array** (convenient for chaining).

## Behavior:

| Property | Description |
|---|---|
| Changes element order | Yes |
| Modifies the original array | Yes |
| Returns | The same array (now reversed) |
| Return value type | `Array` |

## Example with text:

```javascript
const letters = ["a", "b", "c"];
const reversed = letters.reverse();

console.log(reversed); // ["c", "b", "a"]
console.log(letters);  // ["c", "b", "a"] - the same object!
```

`letters` and `reversed` are **the same array**,
because `reverse()` returns a reference to the original object.

## If you want to keep the original

If you need to reverse **without changing the original array**,
make a copy first:

```javascript
const arr = [1, 2, 3];
const reversed = [...arr].reverse();

console.log(arr);      // [1, 2, 3]
console.log(reversed); // [3, 2, 1]
```

## Can also be used with strings:

Strings do not have a `reverse()` method,
but you can achieve it via an array of characters:

```javascript
const str = "hello";
const reversed = str.split("").reverse().join("");

console.log(reversed); // "olleh"
```

## Summary:

| What it does | Reverses the order of elements |
|---|---|
| Mutates the array | Yes |
| Returns | The modified array |
| Safe version | `[...arr].reverse()` |
| Example | `[1,2,3].reverse()` -> `[3,2,1]` |

> **In short:**
> `reverse()` rearranges the array's elements **in reverse order**,
> **modifying the original array**.

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