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// Create an array of numbers
const numbers = [1, 2, 3, 4, 5];

// Find the index of 3 using the indexOf() method
const index = numbers.indexOf(3);
console.log('index: ' + index); // 2

// Check if 3 is in the array using the includes() method
const hasThree = numbers.includes(3);
console.log('hasThree: ' + hasThree); // true

# Array Methods - indexOf, lastIndexOf, includes

Let's explore methods used to find a specific element in an array.

<br />

## indexOf

Finds a specific element in an array and returns its index. If the element is not found, `-1` is returned.

```javascript title="Example of indexOf() Method"
const fruits = ['Apple', 'Banana', 'Cherry', 'Apple'];
const index = fruits.indexOf('Apple');

console.log(index); // 0
```

In the example above, "Apple" is at index 0 in the array, so `0` is printed.

<br />

## lastIndexOf

Finds the last occurrence of a specific element in an array and returns its index. If the element is not found, `-1` is returned.

```javascript title="Example of lastIndexOf() Method"
const fruits = ['Apple', 'Banana', 'Cherry', 'Apple'];
const lastIndex = fruits.lastIndexOf('Apple');

console.log(lastIndex); // 3
```

"Apple" last appears at index 3 in the array, so `3` is printed.

<br />

## includes

Checks whether a specific element exists in an array. Returns `true` if it exists, otherwise `false`.

```javascript title="Example of includes() Method"
const fruits = ['Apple', 'Banana', 'Cherry'];
const hasApple = fruits.includes('Apple');

console.log(hasApple); // true
```

In the example above, since the array contains "Apple", `true` is printed.

The includes() method checks whether a specific element is included in an array and returns true if it is present, or false otherwise. It is useful, for example, when verifying if an array contains 'apple'.

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