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The `push()` method is one of the most frequently used in JavaScript.
It **adds one or more elements to the end of an array**
and **returns the new length of the array**.

---

## Example:

```javascript
const fruits = ["apple", "banana"];
const newLength = fruits.push("cherry");

console.log(fruits);     // ["apple", "banana", "cherry"]
console.log(newLength);  // 3
```

- The method **modifies the original array (mutates it)**.
- It returns not the array itself, but **the number of elements after adding**.

---

## You can add several elements at once:

```javascript
const arr = [1, 2];
arr.push(3, 4, 5);

console.log(arr); // [1, 2, 3, 4, 5]
```

---

## Behavior:

- Elements are added **to the end of the array**.
- The indexes of the new elements start at the current `length`.
- The return value is the new value of `arr.length`.

---

## Important:

- `push()` only works **with arrays** (or array-like objects).
- If you do `arr = arr.push(...)`, you lose the array itself:

```javascript
  const arr = [1, 2];
  arr = arr.push(3); // mistake - arr becomes a number (3)
  ```

---

## In short:

| What it does | Adds elements to the end of the array |
|---|---|
| Modifies the original array? | Yes |
| Returns | The new length of the array |
| Can add several elements | Yes |
| Example | `arr.push(1, 2, 3)` |

---

## Alternative (without mutation):

If you want to add an element **without changing the original**:

```javascript
const arr = [1, 2];
const newArr = [...arr, 3];

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

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