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The `label` operator (or a **label**) is a **rare and rarely used tool** in JavaScript that lets you **give a name to a block of code or a loop**, and then **control execution** with `break` or `continue`, specifying **exactly which loop to stop or continue**.

---

## Syntax

```javascript
labelName: {
  // statements
}
```

Or, most often:

```javascript
labelName:
for (let i = 0; i < 5; i++) {
  ...
}
```

---

## Why `label` is needed

It is usually used when there are **nested loops**, and you need to **exit not just the inner one but also the outer** loop at once.

Without labels, `break` and `continue` only affect the nearest loop.

---

## Example without a label

```javascript
for (let i = 0; i < 3; i++) {
  for (let j = 0; j < 3; j++) {
    if (i === 1 && j === 1) break;
    console.log(`i = ${i}, j = ${j}`);
  }
}
```

**Result:**

```javascript
i = 0, j = 0
i = 0, j = 1
i = 0, j = 2
i = 1, j = 0
```

Here `break` stops only the **inner loop**, and the outer one (`i`) continues.

---

## Example with a label (`label`)

```javascript
outerLoop: // a label for the outer loop
for (let i = 0; i < 3; i++) {
  for (let j = 0; j < 3; j++) {
    if (i === 1 && j === 1) break outerLoop;
    console.log(`i = ${i}, j = ${j}`);
  }
}
```

**Result:**

```javascript
i = 0, j = 0
i = 0, j = 1
i = 0, j = 2
i = 1, j = 0
```

Here `break outerLoop` stops **the entire outer loop**, not just the inner one.

---

## Example with `continue` and a label

You can also **skip an iteration of the outer loop** when a condition is met:

```javascript
outer: for (let i = 0; i < 3; i++) {
  for (let j = 0; j < 3; j++) {
    if (j === 2) continue outer; // skips the current i
    console.log(`i = ${i}, j = ${j}`);
  }
}
```

**Result:**

```javascript
i = 0, j = 0
i = 0, j = 1
i = 1, j = 0
i = 1, j = 1
i = 2, j = 0
i = 2, j = 1
```

---

## Important

- Labels do not create new scopes: they are **just names** that `break` or `continue` can refer to.
- You cannot use `label` for arbitrary jumps, like `goto` in other languages (for example, C).
- Code with labels is often considered **less readable**, and they are **used extremely rarely**: only when there is no elegant way to exit nested loops without them.

---

## The short way to remember it

| What it does | Example |
|---|---|
| Gives a name to a loop or a block | `outer: for (...) { ... }` |
| Lets you exit the outer loop | `break outer;` |
| Lets you skip an iteration of the outer loop | `continue outer;` |
| Does not create a new scope | Yes |
| Use it often? | No, only when needed |

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