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---
title: JavaScript Tutorial | Learn JavaScript - Scaler Topics
description: Basic to advanced JavaScript tutorial for programmers. Learn JavaScript with step-by-step guide along with applications and example programs by Scaler Topics.
author: 
category: JavaScript
---

:::section{.main}
## What is JavaScript?
JavaScript is a very powerful language. It has the power to add interactivity to static websites(built using `HTML and CSS`), apply dynamic styles, add or delete HTML elements dynamically, and much more. So, whenever you try to submit an empty form and an error message pops up, you should know that it's JavaScript behind that!

JavaScript is the language of browsers. Whenever we write JavaScript, the browser will execute that code for us. If we want to write JavaScript away from browsers, we need Node.js, which is the run-time environment for JavaScript. It is used to write JavaScript for back-end. 

Hence, JS can be used to add interactivity to the front-end of the web-apps and create servers to run back-end using Node.Js. This JavaScript tutorial explains everything in detail.
:::
:::section{.main}
## Why Should You Learn JavaScript?

If you want to explore the web and see how interactions work on websites and web applications, you MUST learn JavaScript.

1. You can use JavaScript to create super-fast websites and web applications. It provides a great experience to the users while interacting with your website.
2. JavaScript is built into almost all modern web browsers by default. No setup or software is required to run JavaScript. `Chrome, Safari, Mozilla Firefox`, or any other web browser you can think of; support JavaScript.
3. You can use JavaScript to create front-end and back-end for your website or web application. JavaScript in its raw form can be used to make front-end for web applications. In addition, we can use frameworks and libraries, like React, Vue, Angular, etc., to primarily make the browser do lesser work and increase speed.
4. For the back-end, we can use JavaScript server-side environments. A popular one is `NodeJS`. It is a run-time environment to run JavaScript on the server-side. In addition, frameworks and libraries such as ExpressJs and `NestJS` can be used.
5. Features of JavaScript have been extended to mobile development and game development. Plus, front-end development is in huge demand in the market.

Considering tons of opportunities and features this language has to offer, every student must learn this language and Boyaa! You will have all the power to experiment with the web and build crazy web applications.

If any of this seems interesting to you, this javascript tutorial is for you.
:::

:::section{.main}
## Features of JavaScript

Below listed are some of the main and popular features of JavaScript:

1. All the modern web browsers have built-in environments for executing JavaScript.
2. It empowers developers to provide a good user experience to their users.
3. JavaScript is a weakly typed language. If you've ever written code in `JAVA or C/C++`, you know what creating types for each variable means. JavaScript frees you to write type-less code.
4. It is case-sensitive and interpreted language. 
5. JavaScript is lightweight and is super fast during execution.
:::
:::section{.main}
## Applications of JavaScript Programming
Today, most developers use JavaScript in some form or the other. JavaScript can be used to -

1. Create super fast and interactive front-end
2. Build back-end for web-applications
3. For Game Development
4. To build mobile applications
5. For client-side validation
6. Manipulating `DOM` (Document Object Model) and `BOM` (Browser Object Model)

to name a few...
:::
:::section{.main}
## JavaScript Example
JavaScript is a versatile programming language that can be used in a variety of ways. Here's an example of how you might use JavaScript to create a simple webpage that greets the user:

```javascript
<!DOCTYPE html>
<html>
<head>
	<title>Hello World</title>
</head>
<body>
	<h1>Hello World!</h1>
	<script>
		alert("Welcome to my website!");
	</script>
</body>
</html>
```

This code creates a basic HTML webpage with a "Hello World!" heading and a JavaScript alert that welcomes the user to the site

:::

:::section{.main}
## How JavaScript makes HTML build-website better?
JavaScript is a crucial component of modern web development because it allows developers to create dynamic and interactive web pages. By using JavaScript, web developers can enhance the user experience by adding animations, form validation, and other interactive features. Additionally, JavaScript can be used to retrieve and manipulate data from APIs, making it possible to create web applications that can communicate with external services.

Overall, JavaScript is a powerful tool for building modern, interactive websites that can engage and delight users.

:::

:::section{.main}
## Useful JavaScript Frameworks and Libraries

There are many valuable libraries and frameworks already built on top of JavaScript, making the client-side and server-side development easy and efficient. These are some of the most commonly used and loved frameworks and libraries used by developers all over the world:

* React.js
* Angular
* Vue.js
* jQuery
* NodeJS
* Express.js
* Ember.js
* Backbone.js
:::
:::section{.main}
## Prerequisites

JavaScript adds interactivity to websites and web applications in its most basic form. So, it is expected that you already know `HTML and CSS`. 

Additional knowledge of Object-oriented concepts will help you get more out of this javascript tutorial course, but it is not necessary to start this course.
:::
:::section{.main}

## What will you Learn in This JavaScript Tutorial?

* This course starts with the very basics of JavaScript including `variables, data types, operators, expressions`, etc. They'll help you write your program using JavaScript language.
* Then, you'll learn how to conditionally program your code using the `if` statement. We'll proceed with `for` and `while` loops, which helps us repeat a certain code snippet a number of times.
* Going a bit deeper, you'll see how to work with Arrays and Objects while handling data. How various operations can be performed on them using functions like `map()`, `filter()`, `splice()`, to name a few.
* Proceeding further with the most important concepts like Asynchronous JavaScript and promises, you'll learn how browsers handle functions that do not send an immediate response.
* This comes with the developer's responsibility to handle any possible errors. Hence, you'll learn how to handle errors effectively and not let them cause a bad experience for your application's users.
* Then, `AJAX and JSON`, i.e. JavaScript Object Notation will be explained in detail with real-life examples.
* Important concepts of Object-oriented language, like inheritance, polymorphism, abstraction and encapsulation will be explained in this javascript tutorial course. This will help you work with classes and objects in JavaScript.

Now, let's start this javascript tutorial course and learn javascript and it's most important concepts in the most effective way possible. Keep coding and experimenting along.
:::
:::section{.main}
## Frequently Asked Questions

### What is JavaScript?
JavaScript is a programming language that is commonly used to add interactivity and functionality to web pages.

### What are the basics of JavaScript?
Some of the basic concepts in JavaScript include variables, data types, operators, functions, and control structures like loops and conditionals.

### How is JavaScript different from other programming languages?
JavaScript is unique in that it is primarily used in web development, whereas other programming languages may be used for a variety of applications. Additionally, JavaScript is a client-side language, meaning that it runs in the user's web browser rather than on a server.
:::


This JavaScript tutorial covers all the important concepts in JavaScript such as operators, loops, functions, OOPs, Asynchronous JS, and much more from the very basics to advanced level. It is best suited for beginners and professionals due to its simple and friendly language. You can follow this tutorial for crystal clear understanding of JavaScript.

JavaScript Tutorial

Client Side Scripting and Server Side Scripting

What is JavaScript?

Hello World Program in JavaScript

How to include a JavaScript file in another JavaScript file?

Difference Between Java and JavaScript

Introduction to JavaScript

Javascript Variables

Type Conversion in JavaScript

What is Type Coercion in JavaScript?

Difference Between Var, Let, and Const in Javascript

JavaScript Data Types

JavaScript Operator Precedence

JavaScript String

Javascript String Search()

Template Literals in JavaScript

JavaScript Number

Null and Undefined in JavaScript

Variables and Datatypes in JavaScript

JavaScript Arithmetic Operators

Difference Between == and === in Javascript

JavaScript Comparison and Logical Operators

Comparison Operators in JavaScript

JavaScript Statements

Operators in JavaScript

JavaScript Ternary Operator

JavaScript if, else, and else if Statement

Switch Case in JavaScript

Loops in JavaScript

Javascript functions

Pass-By Value and Pass-By Reference in JavaScript

JavaScript Anonymous Functions

How to Pass Parameter in JavaScript Function? 

Closure in JavaScript

Conditional Flow in JavaScript

Javascript Array

JavaScript Array Iteration

Array Method in JavaScript

Array Sort in JavaScript

Arrays in JavaScript

What is Prototype Inheritance in JavaScript? 

JavaScript Built-in Objects Part 1 

Built-in Object in JavaScript

Map and Set in JavaScript

Working with Objects in JavaScript

this Keyword JavaScript

JavaScript new Keyword

JavaScript Constructor Function

Inheritance in JavaScript

Encapsulation in JavaScript

JavaScript Static Methods

OOP in Javascript

JavaScript Getter and Setter

JavaScript Events

Event Handling in JavaScript

Javascript Classes

Asynchronous JavaScript

Promises in JavaScript

Event Loop in JavaScript

Async/Await in JavaScript

Async in JavaScript

JavaScript try...catch

Console in JavaScript

Error Handling in JavaScript

What is JSON?

parse() JSON JavaScript

JSON Vs XML - Difference between JSON and XML

What is AJAX?

Difference Between JavaScript and jQuery

Extras