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SF AppWorks Feb 20, 2020 5:12:00 AM 5 min read

What Is React JS? | SF AppWorks

What exactly is React JS? A framework? A library? Essentially, React JS is a front-end web developer’s tool that makes for a streamlined workflow. It has the functionality of a framework and the bones of an open-source JavaScript library.


At SF AppWorks, we aim to help your business stay modern by developing software and apps for you. In this article, we’ll be discussing all things React JS, including what it is, how it works, essential features, and other answers to your burning questions. 


Related: 10 Powerful Benefits of Programming Outsourcing in 2020


What is React JS?


To put it simply, React JS is a tool used in web development. It’s an open-source JavaScript library that’s used to build interactive elements on single-page applications. These interactive elements enable you to build user interfaces and web applications that can change data without a page reload. In addition to being an open-source library, React JS also acts as a framework. 


A “library”—if you’re not familiar with web development jargon—is essentially a pre-written extension, containing the fundamental functions such as the Parent Codes. A “framework” refers to the collection of JavaScript libraries, which are what your websites and web applications are built around. Think of the libraries and frameworks as your architectural blueprints for your website.


What is Javascript?


JavaScript (JS) is a scripting or programming language designed for performing dynamic tasks within a single web page or application. For example, when you see an animation or a search box, that is a dynamic task written by a developer using JavaScript. 


JavaScript is designed to work and run within the HTML structure of each website, offering interactive elements and complex features that bring the web page to life. For those who are less code-savvy, JS is its own language of coding built into your web browser and used to make websites more attractive to its viewers.


Why do Javascript Developers Use React?


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Why use React?—Javascript developers use React to create a more streamlined workflow. As mentioned above, React is a JavaScript library that specializes in developing user interfaces (UIs). This includes websites and web applications that have on-screen menus, search bars, and other clickable buttons that allow the user to interact with the website. 


Before React came about, web developers had to use raw language. In other words, they had to write everything out themselves, which took up more time and left more space for bugs and mistakes. React essentially allows for writing JavaScript code in shorthand. 


Ready to get started on your company’s app? Find out more about our developers about SF AppWorks.


Why Use React JS?


Here’s what we know so far: 


React JS is used to build user interfaces with reusable UI components since it acts as an open-source library, and it’s used to handle the view layer for the web on mobile applications. In addition, because you can reuse code, developers don’t have to write everything out in raw form, which saves time and minimizes errors.


In addition to all of this, React JS has two key features that developers find incredibly helpful:




JSX is short for JavaScript eXtension - it’s a React eXtension that makes life easier for web developers by allowing them to modify their DOM with simple HTML-style code. The DOM is the Document Object Model, which is basically the layout of a webpage. 


Web browsers read HTML documents and display them on your device as web pages. When the browser is reading the HTML documents, it creates the DOM for the page and displays the information accordingly. Developers can modify the DOM with JavaScript to create a bolder arrangement. 


JSX is used to update and modify the DOM more efficiently, especially since it’s compatible with all web browsers.


Virtual DOM


For the more interactive websites that aren’t using JSX or React, the DOM modifications will result in a much slower reload time. Of course, if the developer is using JSX to modify and update its DOM, then React JS will automatically create a Virtual DOM.


The Virtual DOM is basically a carbon copy of the site’s DOM. React JS uses this copy to scan and analyze which parts of the primary DOM need to be changed when an interaction happens (i.e., when a user clicks a button). 


This allows for selective updates and modifications rather than whole updates that would reflect any changes that happen. This takes up less loading and less computational power, which becomes extremely valuable when a website is filled to the brim with content and relies on heavy user interaction.


Is React JS a Framework or a Library?


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Is React JS a framework? Or, is it a library? 


If you’ll recall, we mentioned that React JS acts as both a library and a framework. Primarily, React JS is an open-source library for building interactive user interfaces. This library, in particular, allows for reusable UIs to cut down on time and to minimize errors. 


While React JS also functions as a framework, it cannot be defined as a framework alone. Basically, if you were to search for the answer on the internet, you would find that most people refer to React JS as a “library with additional framework functionality”. What a framework does, essentially, is it allows for the inversion of control. In other words, it’s there to solve architectural and structural problems on a coding level. 


But in React JS, the framework functionality doesn’t actually solve any architectural or structural problems. Instead, it serves the purpose of providing the developer with a set of methods to handle said problems. In fact, React JS does not work within any template design pattern nor does it push the structure of applications in any direction. 


Its framework functionality hangs in the balance of being able to handle view with the input framework—which React JS handles pretty well. 


React JS Examples


To give you a clearer picture of what React JS is exactly, we’ve compiled a list of React JS projects for you to take a look at. These projects were all created by the React JS community:



You can view more React JS examples from the community here and also here.


Should You Familiarize Yourself with React JS?

 file_manager  as a concept of what is react js

The answer here is simple—yes. React JS is arguably one of the best tools out there to help you successfully and efficiently build user interfaces with minimal issues. Understanding React JS will help you better communicate with your app, software, and web developers to take your business to the next level. If you’re ready to get started on developing an app for your business, start here with SF AppWorks.

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