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## 1. **The** `delete` **operator**

The simplest and most common way:

```javascript
const user = {
  name: 'Tim',
  age: 25,
  city: 'Kyiv'
};

delete user.age;

console.log(user);
// { name: 'Tim', city: 'Kyiv' }
```

The `delete` operator removes a property **directly from the object**.

---

### Important:

- `delete` only works **with object properties**, not with variables.
- It returns `true` even if the property did not exist:

```javascript
  delete user.nonexistent; // true
  ```
- It **does not affect the prototype**, only the object itself.

---

## 2. **Via destructuring** (an immutable approach)

If you want to **create a new object without a property**,
without changing the original:

```javascript
const user = { name: 'Tim', age: 25, city: 'Kyiv' };

const { age, ...updatedUser } = user;

console.log(updatedUser);
// { name: 'Tim', city: 'Kyiv' }
```

Here `...rest` collects all the remaining properties,
so the removal happens "softly", without changing the original.

---

## 3. **Using** `Reflect.deleteProperty()`

This is a modern alternative to `delete`, equivalent in meaning,
but used in more formal scenarios (for example, in metaprogramming).

```javascript
const user = { name: 'Tim', age: 25 };
Reflect.deleteProperty(user, 'age');

console.log(user); // { name: 'Tim' }
```

The behavior is the same as `delete`, but it returns `true`/`false` more strictly.

---

## 4. **Nulling out or reassigning (when you do not need to physically remove it)**

Sometimes it is safer not to delete, but just to clear the value:

```javascript
user.age = null;   // value logically removed
// or
user.age = undefined;
```

Such a property stays in the object,
but its value is considered "empty".

---

## Summary

| Way | Changes the original object | What it does | Note |
|---|---|---|---|
| `delete obj.key` | Yes | Removes the property | Simple and common way |
| `Reflect.deleteProperty(obj, key)` | Yes | The same, but "officially" | Used in metaprogramming |
| Destructuring `{ key, ...rest }` | No | Creates a new object without the property | Immutable approach |
| `obj.key = null` | Yes | "Clears" the value but does not remove the key | Handy when resetting state |

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