JavaScript Libraries

By Martin Williams
Published on April 16, 2020
JavaScript Libraries

JavaScript is an integral part of any web application and its importance continues to grow. With the expanded demands, an easier means to interface with JavaScript in web development became increasingly important. Web developers could, if they wanted to waste a lot of time, continue to write their own code for everything they needed. On the other hand, a good programmer knows when to use a code that has already been written by someone else but works for their current need.

An example of when and why to use a preexisting JavaScript code can be seen in something as simple as a contact form. Regardless of the fields and questions that you want in a contact form, chances are that someone else has created it. You could spend time writing your own code for this simple addition to your website, or you could use a code that someone else has already written.

This is the the beauty of JavaScript libraries. In the web development world, certain JavaScript codes can be used again and again for different sites. A library is a JavaScript file that contains numerous functions that are documented with a list of available functions and what they do. JavaScript libraries are very useful in that they save web developers time and headaches by giving them pre written codes that are proven to work.

The following list is 10 of the best JavaScript libraries that are available and some of the functions that they contain. There are numerous libraries out there, but these 10 are a perfect introduction to what a good JavaScript library can do for you.


One of the oldest and most often used JavaScript libraries out there. In fact, some estimates put jQuery usage at about 50% of the websites out there. The primary use of jQuery is Document Object Model (DOM) manipulation which basically means it defines the logical structure of documents and how they can be accessed and manipulated. There are also many plugins that help perform tasks needed in web development. Some of the features of jQuery include:

  • CSS manipulation
  • HTML/DOM manipulation
  • HTML events
  • animations and effects
  • Utilities
  • Ajax

Maybe the best feature of jQuery is the way it handles broker incompatibilities without intervention from a developer. While some websites insist that jQuery is no longer needed, and in rare cases it can actually hurt the effectiveness of a site. Until things change dramatically, jQuery is still one of the most important libraries out there.


The "D3" stands for data driven documents and is a great tool for creating custom visualizations. Documents are manipulated based on the data received and that data can be received in any format. This library has a powerful API that uses selectors similar to those in jQuery, and after an element is selected there are many possible manipulations and translations. The latest version is a collection of 30 modules each with a different purpose in terms of creating visuals. It is also easy to debug and saves a developer many lines of code because of its declarative approach.


Created by a former employee of Facebook, React is an open source library backed by Facebook and used in many sites around the world. React is used to create large or small scale web applications and has a specific usefulness in creating interactive websites such as Facebook. React is a single page application (SPA) because it can fit on a single page and does not need constant refreshes from the browser. React uses JSX, which can be confusing because it relies entirely on JavaScript rather than one of the other JavaScript libraries, but it is clear how useful it is over time. For instance, JSX makes it simple to use JavaScript in your HTML. If you are a front end web developer, then React is a great tool for you.

Dojo Toolkit

Another one of the open source JavaScript libraries, the Dojo Toolkit helps develop cross-platform, JavaScript, and Ajax-based websites in a faster manner. Dojo has a large set of APIs and modules, and there are several parts to a Dojo toolkit including:

  • dojo – The core modules.
  • dijit – A user interface module that helps with layout and widgets.
  • Util – Includes utilities and build tools for testing, style checking, and more.
  • dojox – Helps with charting, grids, and DTL.

Dojo is simple to use and has a lot of both formal and community support associated with it. In addition, the documentation is top-notch and thorough so you will not waste time trying to figure out what it can and cannot do.


Glimmer is the smaller version of the Ember JavaScript framework. Ember was created to handle all of the tasks and coding that is common to every web app and that programmers used to have to do by hand. Glimmer has taken that huge framework and made it lightweight and fast. In fact, the Glimmer tagline is "Fast and light-weight UI components for the web" and that is exactly what it is.


A Google created web based visual programming editor. When you add this to the code, the library adds a an editor to the app that represents snippets like expressions, loops, variables, and more as blocks. These blocks allow developers to create scripts and programs with a drag-and-drop function even if the developer knows little to nothing about the code needed. Each block represents a chunk of code that can easily be stacked and translated. There are no server side dependencies with blocky as it is a completely client side library.


While many JavaScript libraries create digital content, very few can match the stunning 2D animation-based images. Pixi is primarily used to create games and interactive websites with a lot of animations. Disney is one of the primary users of this library as they use Pixi.js to create most of their digital content. Pixi is straightforward to learn and is the perfect next step if you have learned Adobe Flash. Pixi does a great job of hiding some of the most complex functions in a simple and ready to use library.


While Pixi is a great with 2D images and animation, the Verge3D toolkit is perfect for creating 3D visualizations on websites. Puzzles, animations, AR/VR and more are all examples of what Verge3D can do. You do not have to be a professional coder or a professional artist to render some great 3D animations and drawings, and it can even be used to help create games. Verge uses WebGL for rendering and realistic colors and PBR materials for a great 3D experience on the web. Verge has been used by NASA to create a 3D experience of what you would see on the planet Mars.


Another one of the most used JavaScript libraries is the Velocity.js. This JavaScript library makes web animation easier and faster than ever. Velocity is a fast performance engine that is at least as speedy as CSS or jQuery. With the world moving more and more toward mobile applications, the fact that Velocity outperforms other libraries in mobile applications which make it an even more desirable tool. With Velocity you can run a sequence of animations one after the other in a neat way without extensive coding. Some of the websites using Velocity include WhatsApp, Uber and HTC.

Google Polymer

Polymer, another of the most commonly used JavaScript libraries, allows you to build encapsulated and reusable web components that work just like HTML elements. You can create more interactive options using HTML, CSS and JavaScript by reusing or creating custom elements. Once Polymer is up and running you can reuse already developed code without worrying about how the code was created. You can also build custom elements that can be used across the network simply by importing the required HTML.


While many of the JavaScript libraries mentioned above add features or save time by providing shortcuts in coding, QUnit is a testing framework. It can test any generic JavaScript code, even on the server side, to ensure that there are no bugs or bad code and then fix it if there are. Now that JavaScript is essential to any web project and manual testing is so complicated and unreliable, QUnit continues to grow in importance. It is powerful and easy to use and unit tests written for one application can be reused across browsers and for other applications.


As JavaScript continues to be vital to almost any web project, JavaScript libraries become more essential. As time passes, new libraries are created and a working knowledge of what libraries are out there are essential to save time, remain accurate, and create better looking websites and applications.

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