What Is React & How Does It Actually Work?

React is the most popular JavaScript library for building user interface (UI). It offers excellent response to user input by utilizing a new method to render websites.

The components of this tool were developed by Facebook. It was launched as an open-source JavaScript tool in 2013. Currently, it remains ahead of its main competitors such as Angular and Bootstrap, two best-selling JavaScript libraries of its time.

In this article, we are going to help you understand what React is and how does it benefit your work as a front-end developer.

Why Use React?

React homepage what is reactReact has been used by hundreds of major companies around the world, including Netflix, Airbnb, American Express, Facebook, WhatsApp, eBay, and Instagram. This is proof the tool does have a number of advantages that cannot be rivaled by its competitors.

Here are some of the reasons to use it:

1. Easy to use

React is a JavaScript open source GUI library that concentrates on one specific thing; completing UI tasks efficiently. It can be categorized as “V” in the MVC (Model-View-Controller) pattern.

As a JavaScript developer, you will find it easy to understand the basics of React. You can even start developing web-based applications using it, in just a couple of days.

To strengthen your understanding, try exploring the many tutorials about React. They contain plenty of information on how to use the tool: videos, tutorial, and data that can enrich your insights.

2. It Supports Reusable Component in Java

React allows you to reuse components that have been developed into other applications that use the same function. The component reusability feature is a distinct advantage for developers.

3. Easier Component Writing

React component is easier to write since it uses JSX, an optional syntax extension for JavaScript that allows you to combine HTML with JavaScript.

JSX is an excellent blend of JavaScript and HTML. It clarifies the entire website structure writing process. In addition, the extension also makes it much easier to render multiple functions.

While JSX may not be the most popular syntax extension, it has proven to be efficient in developing special components or high-volume applications.

4. Better Performance with Virtual DOM

React will efficiently update the process of DOM (Document Object Model). As you might know, this process can cause a lot of frustration in web-based application projects. Luckily, React uses virtual DOMs, so you can avoid this problem.

The tool allows you to build virtual DOMs and host them in memory. As a result, every time there is a change in the actual DOM, the virtual one changes immediately.

This system will prevent the actual DOM to force the updates continuously. Therefore, the speed of your application will not be interrupted.

5. SEO Friendly

React allows you to create a user interface that can be accessed on various search engines. This feature is a huge advantage because not all JavaScript frameworks are SEO friendly.

In addition, since React can speed up your application process, it can also improve your SEO results. After all, your web speed plays a huge role in SEO optimization.

However, you should note that React is just a JavaScript library. This means that it cannot do everything by itself. The use of additional libraries might be needed for state management, routing, and interaction purposes.

How Does React Work?

You might be surprised to know that you can write HTML codes in JavaScript. But this is exactly how React works.

Creating the representative of a DOM node can be done through creating the Element function in React. Here is an example of it:

React.createElement("div", { className: "red" }, "Children Text");
React.createElement(MyCounter, { count: 3 + 5 });

As you might have noticed, the syntax in the HTML code above is very similar to XML components. However, instead of using traditional DOM class, React uses className.

JSX tags have a tag name, children and attributes. The quote marks in JSX attributes represent strings. This element is similar to JavaScript.

In addition, numeric values and expressions must be written inside a curly brace.

The example above greatly illustrate the syntax in React since the tool use the JSX extension. Basically, it is a combination of HTML and JavaScript.

Here is an example of React written using JSX:

<div className="red">Children Text</div>;
<MyCounter count={3 + 5} />;
var GameScores = {player1: 2,player2: 5};
<DashboardUnit data-index="2">
<h1>Scores</h1><Scoreboard className="results" scores={GameScores} />

To break it down, here are some notes regarding the HTML tag above:

  • <MyCounter> represent a quirk called “count” that shows numeric expression as its value.
  • GameScores is an object literal that has two prop-value pairs.
  • <DashboardUnit> is the block of XML that gets rendered on the page.
  • scores={GameScores}: the scores attribute gets a value from the GameScores object that was defined earlier.

Most part of React is written using JSX (JavaScript XML) rather than standard JavaScript (JS). However, you should note that the only purpose of this is to make the React components easier to create.

You can create React component with standard JavaScript, but we guarantee that it will be super messy.

Furthermore, the idea behind the use of JSX in React was that Facebook (as the initial developer)  wanted to provide one particular type of syntax extension with a clear and unambiguous configuration for developers.


Finally, we hope that this article could give you some insights about what react is and how does it actually work. To conclude it all, here are some important notes regarding the subject:

  1. React was originally introduced by Facebook.
  2. It is used by a lot of major brands and companies around the world.
  3. React serves as a JavaScript library. However, it can also be categorized as a framework.
  4. This framework cannot work alone, you are going to need additional elements for various purposes such as routing, management, etc.
  5. React uses virtual DOM to provide better optimization of your page.
  6. This framework is easy to use and is SEO friendly.
  7. Supports component reusability.
  8. Uses JSX extension, which basically is an excellent combination of HTML and JavaScript.
  9. React uses JSX just to make it easier to write, not because it performs better.
The author

Andrew Vickers

Andrew is a passionate WordPress developer. He loves picking apart source code and learning new things. When he’s not working, Andrew likes to hike and play video games.