JavaScript is the most widely used programming language on the planet. But what is JavaScript exactly and what makes it so popular? To find out, let’s take a closer look at this fundamental programming language.

How Is JavaScript Used?

JavaScript began as a language used exclusively on the front end of websites, but it’s now used in a wide variety of ways.

1. Websites

JavaScript was originally created to bring life to boring, static websites and make them more interactive; it still plays that same essential role in the creation of websites today. In fact, JavaScript is used on more than 97% of all websites currently in existence. JavaScript makes it possible for websites to:

  • Display animations
  • Zoom in or out on an image
  • Generate pop-up windows
  • Progress through a carousel of images
  • Display a series of tabs on a website
  • Validate information from the back end
  • Reveal or hide information by clicking a button
  • Alter a button’s color when the mouse cursor lingers over it
  • Record information in Cookies to provide site analytics
  • Provide additional options through drop-down menus
  • Customize control of in-browser audio and video

In essence, JavaScript makes web pages more dynamic and engaging. Without it, the appearance of websites would change dramatically and be a lot less interesting for users to interact with.

2. Web Applications

Web browsers and computers have come a long way since JavaScript was first introduced in 1995. Along with the changing technology, websites grew to become even more complex and interactive, evolving into what we now know as web applications. Just like with basic websites, web applications rely on JavaScript to add interactivity and engage users, which makes it a vital tool in the field of modern web development. Examples of web applications built on JavaScript include Facebook, PayPal, LinkedIn, Netflix, Amazon, Twitter, and Pinterest, just to name a few.

3. Games

JavaScript is also used in the creation of browser games. Developers can take advantage of JavaScript frameworks designed specifically for game development called “game engines” to simplify the coding and create games more easily. Some of the most popular games that rely on JavaScript include Candy Crush, Bejeweled, and Angry Birds.

4. Back End Servers and Applications

While JavaScript was originally created to work on the client side of websites, it has now become a popular option for the server side thanks to Node.js, a JavaScript Runtime Environment (RTE). Node.js is used on the back end to build web servers, develop scalable network applications, and handle updates from the front end. It's fast, lightweight, easy to learn and maintain, capable of handling large workloads without becoming overburdened, and works on a variety of platforms, which has made it a top choice for Back End Web Developers across the globe.

5. Mobile App Development

In the past, Mobile App Developers had to use a different language depending upon which operating system the app would be published on. For example, Swift was the chosen language for iOS while Java was typically used for Android apps. Now JavaScript is being used more widely in mobile app development thanks to a user interface (UI) framework called React Native. This framework, which was developed by Facebook to improve the performance of their own mobile app, allows developers to create apps that can easily work across multiple platforms.

And More

The list provided above is in no way exhaustive; these are just the primary uses of JavaScript. Thanks to its utility and flexibility, JavaScript is used in an even wider variety of contexts such as presentations, artificial intelligence (AI), desktop applications, virtual reality, and more.

What are the Most Commonly Used JavaScript Frameworks and Libraries?

There are a wide range of JavaScript libraries and frameworks in use today, each with their own unique set of features. According to Stack Overflow’s 2021 survey, these are the ones most commonly used by programmers:


React is a front end JavaScript library created by Facebook to streamline the creation and management of user interface (UI) elements. In Stack Overflow’s 2021 survey, React was ranked as the most commonly used library or framework among professional programmers with 41% reporting extensive use in the past year.


jQuery is a lightweight front end library that allows developers to add functionality to websites while simplifying the coding process and standardizing interactions that occur between HTML elements and JavaScript code. One of the most widely used libraries in the world, jQuery can currently be found on more than 78% of all existing websites.


Express.js is a back end framework that works in tandem with Node.js. The most popular back end framework among professional programmers, Express.js is used to simplify the creation, organization, and maintenance of server-side architecture.


Angular is a popular front end framework used to simplify the development and testing process. Created by programmers at Google, Angular is considered an all-in-one framework because it addresses a variety of the complications developers encounter when building single-page applications (SPA).


Created by a programmer at Google as an alternative to Angular, Vue.js is a front end framework that’s prized for its simplicity and adaptability. Vue is often called a “progressive” framework because developers can easily add components and adapt the framework to meet their needs.

Why is JavaScript so Popular?

JavaScript consistently ranks as the most used programming language in the world. But why is it so popular? Here are a few reasons:

  • JavaScript has a fascinating creation story that has become almost mythical in the programming community
  • JavaScript can be used on both the client and server sides for end-to-end programming
  • Compared to many other programming languages, JavaScript is easy to set up, learn, and use
  • There are many modern JavaScript frameworks and libraries that provide structure, simplify coding, resolve common development issues, optimize tasks, and improve functionality
  • JavaScript is faster, simpler, and more scalable than most other programming languages
  • JavaScript is an open standard, not owned or controlled by one specific corporation or entity
  • Unlike most languages, JavaScript can run everywhere—on the front or back end of any website, browser, desktop, tablet, or mobile phone
  • JavaScript is an accessible language that can be used by beginning, intermediate, and advanced programmers
  • It's supported by an active, thriving community that contributes to its growth
  • JavaScript is updated frequently and continues to evolve to meet the needs of developers

What Do JavaScript Job Prospects Look Like?

The job outlook for those with JavaScript skills is very promising. According to the United States Bureau of Labor Statistics, an estimated 25,500 jobs in web development and design are expected to open up each year between now and 2030. That equals a 13% rate of growth, which is significantly higher than the 8% average growth rate for all occupations.

Jobs that require JavaScript skills also tend to pay well. While the median wage across the country equals roughly $52,000, Web Developers and Designers earn an average salary of $72,500—that’s more than $25,000 higher than what the average American worker earns!

But that’s just the median salary for Web Developers; the earning potential is much higher if you specialize by working as a Front End, Back End, Full Stack, or JavaScript Developer. In these roles, you can earn between $103,000 and $117,000 on average. The pay rate can also increase when you factor in your location, education, and years of experience.

How Can I Learn JavaScript?

You can learn JavaScript in practically any way you’d like—through books, videos, websites, classes, etc. If you have the self-discipline to learn independently, you can find lots of free resources available online including the full text of the book Eloquent JavaScript and a beginner’s guide called JavaScript for Cats.

For most people, however, picking a new programming language without any outside guidance proves to be too challenging and they soon give up. Thankfully, there are plenty of JavaScript classes offered for those who require structure, training, and feedback in order to learn.

You can even learn JavaScript comfortably from your own home through live online JavaScript classes. If you’re looking to acquire JavaScript as part of a broader education, you could enroll in a web development bootcamp to gain all the skills you need to start a new career in web development. The options are endless—it’s simply a matter of choosing which route best fits your goals and preferred learning style.