# Arrays in JavaScript

### What is an array?
We all know what is an array, it is a collection of similar data elements stored at contiguous memory locations.

### How to create an array in javascript?
We can create an array using two ways:

**1. By using an array literal:** an array literal is `[ ]`. It is the easiest way to create an array. For example:

`const cars = ["Tiago", "Safari", "Indigo"];`

**2. By using the `new` keyword:** 

`new` is a keyword in javascript used to create an instance of an object that has a constructor function. For example: 

`const cars = new Array("Tiago", "Safari", "Indigo");`

### How to access elements of an array?

We can access any element in an array, easily by using array indices. 

**Now what is an index?**

Basically, the index is the location of an item in an array. **It starts with 0 **and goes to the length of array - 1.

Now, come to our question how to access an array element? For example:

```
const cars = ["Tiago", "Safari", "Indigo"];

// to access first element 
console.log(cars[0]);

// to access last element
console.log(cars[2]);
```

![Screenshot (117).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661621457756/PwOfaGZPj.png align="left")

### How to add an element to an array?
We have created an array, we know how to access elements of the array. Now let's take a look at how to add elements to an array.

We can add elements to an array by using:

**1. By using the `push()` method:** It adds the element at the end of the array. For example:

```
const cars = ["Tiago", "Safari", "Indigo"];

//adding an element at the end
cars.push("Nexon")

// getting all the elements stored in the array
console.log(cars);
```
Here is the result,

![Screenshot (118).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661622051966/v8L1kMuvO.png align="left")


**2. By using the `unshift()` method:** it adds the element at the beginning of the array. For example:

```
const cars = ["Tiago", "Safari", "Indigo"];

//adding an element at the beginning
cars.unshift("Tigor");

// getting all the elements stored in the array
console.log(cars);

```

See the result, 

![Screenshot (119).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661622315707/IMESix4Qo.png align="left")

Suppose, an array has two elements, and if I add an element at the third index then what will happen? Let's take a look.

```
let country = ["India", "Japan"];

// adding element at index 3
country[3] = "Korea";

// getting the array country
console.log(country);
```

![Screenshot (120).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661623239804/5lY2AD83O.png align="left")

The output says empty at index 2. So, if we try to add elements at higher indices, the indices in between will have an empty value.

### How to remove elements from the array?

We can remove elements by using:

**1. Using the `pop()` method:** It is used to remove the last element from the array. For example:

```
let country = ["India", "Japan", "Korea"];

// removing last element
country.pop();

// getting the array
console.log(country);
```

![Screenshot (121).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661623723307/Ol6xw9iLQ.png align="left")

**2. Using the `shift()` method:** It is used to remove the first element from the array. For example:

```
let country = ["India", "Japan", "Korea"];

// removing first element
country.shift();

// getting the array
console.log(country);
```

![Screenshot (122).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661623947467/csGlFilMW.png align="left")


### How to find the length of the array?

Sometimes you'll need to find the length of the given. In that case, you can use the   `length` property to find the number of elements in an array. For example:

```
let country = ["India", "Japan", "Korea", "USA", "Russia"];

// getting the length of the elements in the array
console.log(country.length);
```
This basically gives 5 as output. 

![Screenshot (123).png](https://cdn.hashnode.com/res/hashnode/image/upload/v1661624344198/hXvDrJGtt.png align="left")