What can we build with JavaScript?

From its simple beginnings as a language to do browser-side scripting, JavaScript has evolved a lot since the first version of the language. There’re now lots of things that we can build with JavaScript that we can’t do before. Here’re some things that we can build with JavaScript today.

Client-Side Apps

JavaScript is still the only language for browser-side web applications. The proliferation of app frameworks like React, Angular, and Vue have made things infinitely easier. Also with ES6+, building client-side apps with JavaScript has been much more pleasant than before. Any other language like TypeScript has to be converted to plain JavaScript before they can run in browsers. All modern browsers support JavaScript and nothing else, so it’s the only language for client-side applications.

Server-Side Web Apps

With Node.js, JavaScript has arrived on the server-side. We can do so much with Node.js, like building a back-end app. There’re various back end frameworks like Express, Nest.js, and many other frameworks that let us write back end apps with ease. It’s so popular that popular hosts like Amazon Web Services have provided SDKs for Node.js, so we can integrate with their services without a hitch. It’s also pretty fast and easy to build back end apps with it.

There’re libraries for interacting with most popular database systems like MySQL and Postgres so we can easily use it for back end apps. If we want NoSQL, there’s also tight MongoDB integration with libraries like Mongoose which lets us interact with MongoDB and provides a schema to save dynamic data.


With Reveal.js and Eagle.js, we can use it easily to build presentations with HTML, CSS, and JavaScript. It provides as much flexibility as PowerPoint but they cost nothing. This is great since it hasn’t been to easy to build presentations with code before these libraries existed.


Once again, Node.js provides a great run-time environment for running scripts. With the fs module, we can do lots of common file and folder operations like add, changing, renaming, and deleting files. Also, changing permissions is easy with it. It also has the child_process module to run processes on any computer the script is running.

Also, Node.js is aware of the differences between Windows and Unix-like systems like Linux and Mac OS, so compatibility issues are minimal when running scripts on any computer.


With HTML5, add interactivity to web pages is easier than ever. This is coupled with the power of JavaScript to make everything dynamic. The Canvas API has lots of methods to draw whatever we want and make them animate.

There’re also game frameworks like Phaser which abstracts out some of the more tedious parts like handling inputs and animations of shapes by abstracting things out into a framework.

Mobile Apps

There’re 2 ways to build mobile apps with JavaScript. One is to write a native app with frameworks like React Native, and the other is to write a hybrid with frameworks like Ionic.

React Native lets us write our app’s code in JavaScript and then compile it into a native mobile app by converting the JavaScript React components into native components of the platforms you’re targeting. Since the framework builds code into native apps, accessing hardware is easier to React Native. It provides built-in support for cameras and accelerometers for example.

Hybrid app frameworks like Ionic let us write apps with HTML, CSS, and JavaScript and then display the code in a browser web view on our mobile devices. Accessing hardware requires native plugins which makes development and testing more difficult. Native plugins are also limited or buggy which is another problem if we try to build apps that need to access hardware with it.

They’re both cross-platform frameworks that let us write our code once and then build them for different platforms.

Internet of Things Programs

We can use JavaScript to build programs that control embedded hardware with frameworks like the Johnny-Five framework. It supports the Arduino single-board computer which we normal load C programs with it.

With Johnny-Five, we can use JavaScript to write our programs which makes writing useful programs a lot easier. It supports full hardware access like LEDs, timers, GPS, motors, buttons and switches, compasses, and more. Of course, this is also thanks to the existence of Node.js since it lets us run JavaScript programs outside the browser.

Desktop Apps

With Electron, we can write desktop apps with JavaScript easily. We can convert React, Angular or Vue apps into Windows, Linux, or Mac OS apps with Electron libraries for these frameworks.

We can also write apps with just the Electron framework alone. It can access things like our computer’s file system so it can do things that a normal desktop program does. However, access to specialized hardware is lacking so it’s more for general business apps. Lots of programs are built with Electron, with the biggest examples being Slack, Visual Studio Code, and the Atom text editor.

We can do a lot with JavaScript. Thanks to Node.js, JavaScript can leave the browser, letting us build apps for Internet of Things devices, back end apps, desktop apps and more. On the browser side, we can use it to build interactive apps like games and rich business apps. We can also make great presentations with it.

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