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## Example of an anonymous function

```javascript
const sum = function(a, b) {
  return a + b;
};
```

This function is **anonymous** because it **has no name after the word** `function`.
It is simply **assigned to the variable** `sum`.

---

## What a named function looks like for comparison

```javascript
function sum(a, b) {
  return a + b;
}
```

Here the function has a name - `sum`.
It can be used inside the function (for example, for recursion) or in the error stack.

---

## Where anonymous functions are most often used

Anonymous functions are most often used:

1. **In function expressions**

```javascript
  const multiply = function(a, b) { return a * b; };
  ```
2. **In callbacks**

```javascript
  setTimeout(function() {
    console.log("1 second has passed");
  }, 1000);
  ```
3. **In arrow functions** (also a kind of anonymous function)

```javascript
  const greet = () => console.log("Hello!");
  ```
4. **In event handlers**

```javascript
  button.addEventListener('click', function() {
    console.log("Button clicked");
  });
  ```

---

## Advantages

Short and concise syntax.
Great for one-off functions, especially as arguments (`callback`).
Used in arrow functions and modern methods (`map`, `forEach`, `filter`, etc.)

---

## Disadvantages

Harder to debug - the error stack does not show the function's name:

```javascript
TypeError at <anonymous>:3:10
```

Cannot call itself recursively (without a name).
Can hurt readability if used too often and nested too deeply.

---

## Example: named vs anonymous in a callback

```javascript
// Anonymous function
setTimeout(function() {
  console.log("Hi");
}, 1000);

// Named function (easier to debug and reuse)
function sayHi() {
  console.log("Hi");
}
setTimeout(sayHi, 1000);
```

---

## Quick summary

| Type | Example | Has a name? | Can be called directly? |
|---|---|---|---|
| **Named** | `function foo() {}` | Yes | Yes |
| **Anonymous** | `function() {}` | No | Only via a variable or callback |
| **Arrow** | `() => {}` | No (anonymous by nature) | Via a variable |

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