Arrays in JavaScript

An array is a unique data structure that holds an ordered collection of elements, which can be of any data type such as numbers, strings, or even other arrays. It allows you to store multiple values in a single variable, which can be very useful in many programming scenarios.

Declaring an Array

In JavaScript, you can declare an array using an array literal. (Note: Array literal is a list of zero or more elements where each one represents an element of the array and each of them has an index. And the whole list will be inside square brackets([]). Elements can be added to an array by separating them with commas.). For example:

let colors = ["red", "blue", "green"];

An array can be declared with a set of elements using the Array constructor:

let numbers = new Array(1, 2, 3);

Also, we can create an empty array and insert elements by accessing the index of the array. [Note: The index starts from 0 and goes up to the number of elements minus one.]

const array = [];
array(0) = "orange";
array(1) = "apple";
array(2) = "mango";

Accessing Array Elements

To access an element in an array, you use its index number. For example:

let colors = ["red", "blue", "green"];
let firstColor = colors[0]; // firstColor will be "red"

Modifying Array Elements

You can modify an array by updating its elements. To do this, you can use the index of the element you want to change and assign a new value to it. For example:

const colors = ["red", "blue", "green"];
colors[1] = "yellow";

Adding Elements to an Array

You can add elements to an array in several ways.

1. Using the push() method

The push() method adds one or more elements to the end of an array.

const colors = ["red", "blue", "green"];
colors.push("purple");

1. Using the unshift() method

The unshift() method adds one or more elements to the beginning of an array.

const colors = ["red", "blue", "green"];
colors.unshift("orange", "pink");

Removing Elements from an Array

You can remove elements from an array in several ways.

1. Using the pop() method

The pop() method removes the last element from an array.

const colors = ["red", "blue", "green"];
colors.pop();

1. Using the shift() method

The shift() method removes the first element from an array.

const colors = ["red", "blue", "green"];
colors.shift();

Array methods in JavaScript

Source

Conclusion

Array in JavaScript is a powerful data structure that allows to store and manipulate of collections of a data set.