JavaScript is used to develop interactive web applications. JavaScript can power featured like interactive images, carousels, and forms. The language can be used with back-end frameworks like Node.js to power the mechanics behind a web page, such as form processing and payments.
JavaScript is one of the three fundamental technologies that power web applications. If you are a newcomer, you may be asking yourself what the JavaScript programming language is.
Before you start learning to code using JavaScript, it is essential you understand its potential uses. This will give you a better sense of whether learning JavaScript is a good investment for you, given your long-term career goals and aspirations.
In this guide, we show you the purposes of JavaScript and explore the main situations where you would use this programming technology.
What is JavaScript?
Every time you see a webpage that does more than show content, you can bet JavaScript is working in the background.
JavaScript allows you to make a website more interactive, from automatically updating content to creating animated graphics and resizing elements on a web page.
HTML and CSS allow you to define the structure of a web page and its style, respectively. These are the two other languages used to build websites. However, if you want to make a site interactive and add content that updates dynamically, you need to use JavaScript.
What is JavaScript Used For?
Now that we’ve explored the basics of JavaScript, let’s tackle the question: what is the JavaScript programming language used for?
While JavaScript may be best-known for front end web development, it has plenty of uses beyond web development. The front-end is the part of a website a user sees. Let’s break down four of the main uses of the JavaScript programming language. Due to its popularity, there are many online JavaScript courses available for beginners.
#1: Front End Web Development
Using JavaScript, you can add dynamic features, such as changing text and content and images that resize themselves to a website. These are user experience changes, which means they visible to the user and how they use the site in their web browser.
Here are a few examples of the front end changes you can make to a website using JavaScript:
- Display information when a button is clicked
- Create a dropdown menu that activates when clicked
- Allow a user to zoom in or out on an image
- Show a series of tabs on a website
- Display animations on a website
- Play audio or video on a web page
#2: Back End Web Development
You can also use JavaScript in combination with tools like Node.js for server-side programming. The back end refers to the behind-the-scenes code that makes a website work on a web server.
For instance, you can use JavaScript with Node.js to save form data to a database. A JavaScript back-end could process payments, save user posts, and do any of the other behind-the-scenes work that a website needs to run.
#3: Mobile Application Development
Traditionally, mobile applications were developed using languages specific to an operating system. For instance, Swift is used for iOS, and Java is used for Android mobile development. However, in recent years, several technologies have been developed that allow you to create mobile applications using the JavaScript programming language.
React Native is one example of these frameworks. It allows you to use JavaScript and React to build an application that runs on a mobile device. Phonegap, maintained by Adobe, allows you to build mobile apps using web technologies. Angular and Vue are some other frameworks you can use for this purpose.
#4: Game Development
JavaScript is used in online games. Many of these games are simple platform games because JavaScript is not as powerful as other languages for building games. You’ll find plenty of online games, like Cookie Clicker, powered by JavaScript on the internet.
There are many limitations to building a browser-based game using JavaScript. But, the language is nonetheless often used by game developers to create simple games. JavaScript by itself does not scale very well if you want to build large games.
For instance, many of the computer games high school students play today have been built using JavaScript. The advantage of using JavaScript for basic game development is that you can create something that runs in the browser. Thus, the user doesn’t have to download anything to make the game work.
Why Do We Need JavaScript?
JavaScript is everywhere on the Internet—there’s no escaping it. In fact, this very web page uses JavaScript in a number of ways to display its contents. For example, the comments box on our blog is powered by JavaScript—when you click to submit a comment, a JavaScript function is run.
To help you better understand how JavaScript is used, we will show a few examples of companies that use it.
#1: PayPal
PayPal has been using JavaScript since the very beginning (again, because it is so fundamental to all websites). However, the online payment company has also experimented with tools like Node.JS to power their web applications.
PayPal has gone as far as to create their own version of the Express JavaScript framework, which they call Kraken JS. This shows how much PayPal uses JavaScript.
#2: Walmart
Walmart’s web application was initially powered by the Java programming language. However, as its site started to grow, the company realized it needed something more efficient.
As a result, Walmart adopted Node.JS. Today the site that renders at Walmart.com uses Node.js to serve web pages.
#3: Facebook
Facebook, the social media giant, uses JavaScript in their projects.
Facebook was responsible for creating React, which to this day remains one of the most popular JavaScript libraries in the world. React is so popular, in fact, that companies, from CloudFlare to the BBC, use it.
Facebook uses React to develop the web versions of the Instagram and WhatsApp platforms. This shows you just how much Facebook relies on JavaScript.
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#4: Netflix
Netflix started off using Java for its web application. However, Netflix engineers decided it took too long to push changes to their site using Java. As a result, they decided to look for another technology to power the site.
Today, Netflix is powered heavily using the Node.Js framework. This back-end framework allows the company to efficiently render content on their website. The move over to Node.Js also allowed them to reduce the burden on their servers, thereby improving the efficiency of their services.
#5: Uber
Uber needs to handle millions of requests every day coming in from drivers and customers. The company needs to work with highly scalable technologies that have a fast speed of iteration.
Uber uses Node.Js and JavaScript to efficiently handle driver requests on its platform. An important part of why Uber chose to use Node.Js is because of the asynchronous features that make it easy to send data.
Conclusion: What is JavaScript Used For?
JavaScript is, first-and-foremost, a web development technology, but it is so much more than that. You can use JavaScript to develop front end and back end web applications. JavaScript is often used to build simple browser games. You can also use JavaScript to create mobile apps.
JavaScript is a popular language. It is often used in combination with third-party frameworks like React, Ember, Node.JS, Vue, Angular, and other tools. These tools provide a number of pre-built functions that extend the usage of the JavaScript framework.
If you’re interested in web development, JavaScript is definitely a skill you should learn!
To learn more about coding with JavaScript, read our How to Learn JavaScript guide.
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