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A detailed guide on JavaScript Web Development

By Mohit Joshi, Community Contributor -

The most widely used programming language in the world, JavaScript has enriched the whole digital realm by enabling developers to build dynamic websites with visually appealing user interfaces. Web Developers that are just starting or seasoned pro developers, everyone is playing with JavaScript, a fundamental route for building successful web applications.

If you’ve lived through the early decade of the century or the pre-JavaScript era, you must have wondered how far things have come across. The websites back then were not only less pleasant but were not even handy. So you might claim that JavaScript does more than just give your websites a pretty face; it also improves their usability and accessibility. If it’s difficult for you to imagine a world without JavaScript, you may just disable JavaScript in your browser and see how you can’t endure the lifeless web pages for more than a few minutes.

In this guide, we are diving into the fundamental understanding of how to leverage JavaScript for web development.

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What is JavaScript for Web Development?

JavaScript is a high-level interpreted programming language that was initially launched in 1995 but came into wider public usage much later. It is an engine that is used for building interactive aspects in the websites that broadens the functionality.

If you come across components in any websites, that utilize animations, maps, graphics, etc., you can be confident that JavaScript is behind all those functionalities. It is a lightweight and object-oriented programming language that is being used by the majority of modern websites available on the internet. It is cross-platform compatible and is supported by all major web browsers.

Both the front end and the back end of websites may be developed using JavaScript, which, when done right, captures seamless communication between the client and the server. The potential of JavaScript to manipulate the DOM is its main benefit for use in modern web development.

Why is JavaScript Important for Web Development?

It is hard to imagine developing user-friendly websites without dealing with JavaScript.  It not only makes the entire development process easier, but it also adds features you wouldn’t get from any other technology. Let’s look at the three top-most important criteria for using JavaScript for web development.

  1. Cross-platform compatibility: JavaScript is supported on almost all modern web browsers present across the world. This has accepted JavaScript as one of the most essential and widely used client-side scripting languages. It not only ensures a seamless experience as a user but also ensures broader coverage of your website as a developer. 
  2. Community Support: Being among the most popular programming languages in the world, JavaScript also ensures a vast collection of resources, tools, documentation, and community support. As a developer, you can go through numerous active forums, tutorials, and open-source projects due to their wide acceptance as a programming language among web developers throughout the world.
  3. Client and Server side capabilities: JavaScript is well-known for building client-side webpages, enhancing the website’s user-friendliness, and adding cutting-edge interactive features. However, as the modern world evolved, JavaScript also expanded its capabilities of scripting the server side of the website with the help of NodeJS.

Different Types of Web Development

Typically, there are two steps involved in creating a website: front-end development and back-end development. In most cases, each part is developed by separate developers with different skill sets, however, When a single developer oversees the entire development of the website, they are known as full-stack developers. Let’s understand both parts of the development and what are their essential features.

  1. Front-end development: It is also known as client-side development, as the name suggests it focuses on the visible parts of the websites that are UI components of an application. This development assures the website is responsive, user-friendly, stylish, and visually appealing in all aspects.
  2. Back-end development: It is also known as server-side development, as it ensures the logic is properly applied on the website as intended by the developer. The developer here creates a behind-the-scene show that powers the website creates a connection of the front end of the website with the required servers and databases, and ensures a seamless transaction of data between them.

Types of Web Development Frameworks

Top JavaScript Frameworks for Web Development

A large ecosystem of frameworks and libraries that use JavaScript and provide several modern features and enhancements essential for web development exists. Since all the frameworks we’re going to talk about are built on JavaScript, learning them won’t take much time if you know JavaScript well.

Let’s look at the top frameworks based on JavaScript for web development.

  • NodeJS: NodeJS expands the capabilities of JavaScript, enabling programmers to build whole applications using only JavaScript. It allows to build a strong back end for any web application without having to learn any new programming language and leveraging JavaScript itself.
  • ReactJS: It is an open-source UI development JavaScript library for developing the front end of websites. A ReactJS website is a collection of several reusable components, each being a building block of the website. The implementation of reusable components using JavaScript has reduced the development time and complexity of development.
  • VueJS: VueJS is an open-source front-end framework used for creating dynamic user-interface and single-page applications (SPAs). Vue.Js enables developers to write code in JSX. However, the components are created in HTML components, therefore, allowing even beginner developers an easy-learning curve.
  • AngularJS: Angular is an open-source full-fledged web application framework based on TypeScript used for creating single-page applications (SPAs). As soon as it was launched, it caught several eyes, due to its excellent features. Moreover, AngularJS gained the enormous trust of developers because it is backed by a tech giant, Google.

Getting Started with JavaScript for Web Development: with Example

You don’t need to rely on any third-party services while using JavaScript for Web Development, and you don’t even need to install a lot of packages in order to start writing JavaScript code.


  1. Install any IDE of your choice. In this example, we are using VS code as our code editor. 

JavaScript Basics for Web Development

To begin with, JavaScript, just like we add CSS, we shall add the following code before the closing body tag in the HTML file to link the JavaScript file.

<script src="script.js"></script>

Note that, our JavaScript file name is “script.js”.

To make sure it works, insert the following line of code in your JavaScript file and view the output in the browser. The alert “hello world” will pop out.

alert('hello world');

JavaScript Web Development Example

1. Variables

Variables are containers of data that can be used to store data of different types such as numbers, strings, objects, and more. To define a variable you may use, ‘var’, ’let’, and ‘const’ keywords. Variables can be used anytime in a document when once define. Let’s understand with an example.

//define a variable
let a = "hello world I am using variable";

//using variable

And the output goes as.

Variables in JavaScript Web Development

2. Operators

You can use JavaScript as a calculator. You can expect JavaScript to support all the basic arithmetic operators. These operators are used wildly in websites for several purposes.
Let’s understand what I’m saying with an example.


Operators in JavaScript Web Development

3. Functions

Functions are reusable blocks of code that are assigned some name to use anywhere throughout the document. Let’s create a function that when given two numbers, returns the output as the sum of those numbers.

//creating a function
function addNumber(a, b){
    let sum = a + b ;
    return sum;

//reusing the function

Functions in JavaScript Web Development

4. Conditional Statements

In a JavaScript file, every code is executed line by line, however, if in some instances, we wish that some code should only be executed under some conditions, otherwise skip the script. This can be achieved by applying conditions in our code with the help of ‘if..else’.

Let’s understand this with the help of an example.

let sum = 2 + 3;

    alert("Sum is greater than or equal to 5");
    alert("sum is lesser than 5");

Conditional Statements in JavaScript Web Development

5. Objects

JavaScript objects are simply key-value pairs or data containers that contain properties and methods. Let’s understand JavaScript objects with the help of an example.

let credentials = {
    id: 'bstackdemo',
    password: 'blue'


Objects in JavaScript Web Development

These were some of the fundamental concepts of JavaScript. Now, let’s unleash the full potential of JavaScript with its most essential feature, which is manipulating DOM. 

Selecting HTML elements and adding an event listener

This part will show us how to really manipulate the DOM using JavaScript. To demonstrate that with an example whenever a button on the website is clicked, an alert is generated. This further demonstrates JavaScript’s dynamic nature. 

Create a button in your HTML file.

   <button class="alert">

Creating Button Element in JavaScript Web Development

First, you have to get the button to operate any related action to it. To do so, there are several methods such as. 

  • getElementById()
  • getElementByClass()
  • getElementByName()
  • getElementByTagName()
  • querySelector()

Further when the HTML element is selected you may use the event listener function to it so it records the event that occurred. For example, if the button is clicked the event listener will record that the button is being clicked.

Let’s create a JavaScript code that creates an alert when the button is clicked.

let button = document.querySelector('.alert');

function alertListener(event) {
  alert("hello you clicked a button");

button.addEventListener('click', alertListener);

Adding Event Listener to an Element in JavaScript Web Development

Best Practices for Using JavaScript Web Development

Now that we have come along so far, we have understood the capabilities of JavaScript, and how it has enhanced modern web development. Let’s now understand how to leverage JavaScript, so that we don’t lag in creating appealing websites. Here are some best practices you must follow to leverage JavaScript for web development.

  1. Constant code style: To maximize efficiency when working on a large JavaScript project that involves developer collaboration, you must ensure that a code pattern and style have been mutually agreed upon. A consistent coding approach makes your code easier to read and prevents misunderstandings with other team members. 
  2. Use proper testing strategies: The process of testing determines if the output product works as intended. If you follow the right testing procedures, your code becomes less susceptible to risks and doesn’t malfunction. Common JavaScript testing techniques include things like avoiding using mock, utilizing try..catch, adopting the BDD approach, and more. 
  3. Keep up with the latest trends: If you stay up to date with the rapid speed of modern web development, you may actively contribute to the creation of user-friendly websites.
  4. Proper Variable nomenclature: You must choose descriptive and meaningful names for variables, functions, and classes. This reduces misunderstanding among the project’s other participants and improves the readability of the code.


A website that engages well with the users stands out among the crowd. In this tutorial, we delved into a detailed discussion of using JavaScript for web development. JavaScript is the most popular and widely-used programming language across the globe. JavaScript has been able to completely change how websites are developed nowadays. 

This article also discussed a number of JavaScript-based frameworks that have altered the development environment by introducing features and tools that lessen the complexity and duration of development while enhancing output. You also got an understanding of different JavaScript code practices that will enable our website to reach a wider audience and work flawlessly in all popular operating systems and browsers.

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