Using in with Arrays

### Syntax:

property in object

### Example with Arrays:
1. **Checking Index Existence in an Array:**

const fruits = ["apple", "banana", "cherry"];

   console.log(0 in fruits); // true (index 0 exists)
   console.log(3 in fruits); // false (index 3 does not exist)
   console.log("banana" in fruits); // false (in checks indices, not values)

2. **Checking for `length` Property:**
The `length` property always exists for arrays.

console.log("length" in fruits); // true

3. **Sparse Arrays:**
The `in` operator can identify gaps in sparse arrays.

const sparseArray = [1, , 3]; // Index 1 is missing
   console.log(1 in sparseArray); // false
   console.log(2 in sparseArray); // true

### Important Notes:
– **`in` Checks Property Names**: It checks if a property (or index) exists, not its value.
– **For Values, Use `includes`**: To check for values in an array, use the `Array.prototype.includes` method:

console.log(fruits.includes("banana")); // true

Would you like an example of another use case or clarification?