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

// Check 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 to find a specific element in an array.

<br />

## `indexOf()`

This method returns the index of the first occurrence of a specified element in the array. If the element is not found, it returns `-1`.

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

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

In the example above, "Apple" is found at index 0, so the method returns `0`.

<br />

## `lastIndexOf()`

This method returns the index of the last occurrence of a specified element in the array. If the element is not found, it returns `-1`.

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

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

"Apple" is found at index 3 when counting from the end, so the method returns `3`.

<br />

## `includes()`

This method checks if a specified element is present in the array. It returns `true` if the element is found and `false` otherwise.

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

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

In this example, the array contains "Apple", so the method returns `true`.

The includes() method checks if a specific element is present in an array and returns true if it is, and false if it is not. For example, it can be used to check if an array contains 'apple'.

### Which array method checks if a specific element is included in the array?