What is React Used For? When and Why To Use React

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Remember the oh-so-precious days when refreshing social media pages and websites to reload user data was the norm? After all, it was the only means of viewing updated information.

However, with the emergence of React in 2011, everything has changed for the better.

Allowing developers to implement more scalable frontends with reloaded information that users can view in real-time.

Now, fast forward nearly a decade later, and nearly every full stack web developer has it as a critical toolkit in their back pockets. React has continually distinguished itself as a declarative, efficient, and flexible frontend Javascript (JS) library used for designing user interfaces on Single Page Applications.

So what’s all the fuss about React in terms of functionality and application? Below, we’ll explore the most comprehensive technical applications and impacts of React for web and app development teams. Keep reading!

What Are the Main Features of React?

As a powerful library integrated and deployed on Facebook’s user interface ever since the early 2010s, ReactJS has distinguished itself for single-page web and mobile applications with sleek user frontend.

By taking advantage of its hallmark feature, data rendering, ReactJS provides the best of both worlds:

  • Fetchable, updated data with sleek front-end design capabilities.

ReactJS primarily targets the DOM of the web page (which we will cover soon).

However, it effectively optimizes efficiency by only updating the part of the DOM which changed, rather than reloading the entire web page.

In the context of UI/UX design and efficiency, ReactJS is critical for emerging mobile and web developers to consider.

Whether it’s ReactJS’s ability to access/establish a virtual DOM or single-way data flow, ReactJS and its continual open source development are scaling in versatility and purpose in the front-end development sector.

Below are React’s most essential features:

1. JSX

Acting as an extension of Javascript syntax, written in a syntax similar to HTML, JSX allows React developers to write ReactJS components.

More specifically, it can be interpreted as a dry combination and mixture of JS and XML. The simplicity of JSX’s syntax allows front-end developers to write components easily.

Ultimately, instead of artificially segregating technologies by essentially placing markup and logic in separate files, React separates concerns with coupled units known as “components” which contain both (markup and logic) in combination.

JSX includes both logic and markup, and unlike AngularJS, it does not require programmers to create separate files for logic and markup. This saves time and creates a more compact/efficient process when creating ReactJS elements.

All in all, JSX presents the following advantages:

  • JSX is notoriously faster than Javascript (by a stretch).
  • Logic and markup are unified and written inside the same file.
  • Programmers can easily create templates in JSX.

Although React does not require JSX, many developers find it handy as an essential visual aid when working UI components inside JavaScript code.

More importantly, it enables React to display useful error and warning messages to better aid debugging.

A simple graphic slide with a snippet of React code that renders a

Related reading: Angular vs. React in 2021: Side-By-Side Comparison

2. Single-Way Data Flow

Otherwise known as unidirectional data flow, Single-Way data flow is not conceptually unique or exclusive to React.

However, for JavaScript developers, it may be the first time acknowledging this feature.

In short, single-way data flow establishes that data has one, and only one, way to be effectively transferred to other parts of the application.

In the context of React, this essentially means that:

  • The state is passed to the view and to child components.
  • Actions will be triggered by the view.
  • Actions update the state.
  • And the state change is eventually passed to the view and to the child components.

This cycle of view, actions, and states is a chain that entirely depends on unidirectional data flow as a principle. The view is a sole result of the application state, the state only changes when actions happen, and in the case an action occurs, the state is updated.

Fortunately, due to the inherent one-way bindings of single-way data flows, data cannot flow in the opposite direction (e.g. two-way bindings).

For both debugging and final deployment, this has several advantages:

  • The data flow is less error-prone, as a single direction ensures more control over your data.
  • It’s effectively easier to debug, as data is traceable. In other words, you know what is coming and from where.
  • Finally, it is hands down more efficient. The library already understands and has defined what the boundaries are in each part of the system.

3. React Native

Ultimately, React Native functions as a framework for building and deploying native applications using JavaScript (JS).

Moreover, in the context of mobile app development, React Native compiles to native app components, which makes it possible to efficiently deploy mobile-ready apps.

Although ReactJS uses React as the base abstraction for React DOM (used for its web platform), React Native uses the same base abstraction but implements React Native (suitable for mobile app environments).

In the end, the syntax and workflow will remain similar and nearly identical, however, the components are different.

As with the vast majority of React’s range of distinguishing features, there are business-level advantages to using React Native which includes the following:

  • React Native is packaged with Native Modules and Native components that optimize performance.
  • Unlike other cross-platform frameworks such as Cordova, and PhoneGap that render code via a WebView, React Native Renders certain code components with native APIs.
  • Remember all the UI-level advantages of React.js? Well, do not fear because those advantages will still remain with React Native!
  • The best part? Applications for iOS and Android don’t need to be developed separately, as React Native enables developers to reuse the common logic layer.
  • React Native’s inherent component-based structure enables developers to create apps with a more agile, web-style approach vs. other development approaches in most hybrid frameworks.
  • If you have a firm grasp of JavaScript, React Native can be naturally picked up, allowing a front-end web developer to mutually learn mobile development.
  • The most essential foundations of knowledge include JavaScript, platform APIs, native UI elements, and platform-specific UI design patterns.
  • Although native app development typically implies suboptimal inefficiency, slower deployment time, and less developer(s) productivity, React Native optimizes speed, responsiveness, and agility of web app development.
  • Additionally, it creates an all-around improved user experience.

Gif image of someone editing react code

4. Virtual DOM (Document Object Model)

Before diving in headfirst into virtual DOM and how it’s manipulated in React, understanding the real DOM is essential.

Simply put, the DOM represents the UI state of your application, as anytime a change in your UI state occurs, the DOM is updated to represent that change accordingly.

Typically, this change in state manipulated the real DOM, resulting in slow performance.

Real DOMs are notorious for having many UI components with many elements/their children that need to be continually re-rendered, leading to a snowball effect of slower performance.

However, a virtual DOM performs significantly better than a real DOM, as it is a real-time virtual representation of the DOM.

When the state of our application is altered, the virtual DOM is effectively updated instead of the real DOM, maximizing efficiency.

Ultimately, a virtual dom optimizes efficiency by calculating the best possible method to make UI changes to the real DOM.

Thus, instead of going through the painstaking process of updating each and every element, a virtual DOM calculates the most performance-efficient approach before updating the real DOM.

Now, how does that mesh with React?

In React, each and every UI piece is defined as a component with each component possessing a corresponding state. React listens for alterations to these states, and when the component’s state changes, Reach updates the virtual DOM accordingly.

Once the virtual DOM has been fully updated, React will proceed to compare the current version of the virtual DOM with its previous version in a process known as “diffing”.

Now, here’s the genius part:

Once React understands which virtual DOM objects have changed, React will only update those objects in the real DOM.

An infographic showing a comparison between the Virtual DOM and the Browser DOM, with a process flow of state change, compute diff, and re-rendering, illustrating the efficient update process in React and how it interacts with the actual DOM for performance optimization.

What Are the Advantages of React?

Whether it means facilitating the element writing process or boosting developer-wide productivity, React distinguishes itself as an open-source leader in the world of JavaScript libraries and frameworks.

React’s core advantages include:

Facilitating the Process of Writing Components

By using JSX as an optional syntax extension to JS, writing components is made easier in conjunction with React.

JSX accepts HTML quoting and effectively makes sub-component rendering easier. As mentioned earlier, JSX detects warning and error messages and prevents code injections, facilitating you throughout the debugging process.

Boosted Productivity

React enables developers to reuse system components and assets. This is, perhaps, the final answer to the long-running question of “Why use React?”

More Efficient Rendering

By using virtual DOMs in conjunction with React, real-time web and mobile application states can be effectively updated for the user, creating a more sleek UI experience while maximizing app performance and processing time.

And finally, many of React’s remaining advantages include:

When Is the Use of React Not Recommended?

The primary reason development teams shouldn’t take on React is if the team members are not the strongest in pure JavaScript as a programming language.

If your frontend team has designers primarily familiar with HTML/CSS, being uncomfortable with JSX, React should not be dumped upon your app development cycle.

All in all, React does not have inherent technicalities that prohibit it from being adopted by the development team.

Rather it is the potential complexities and apparent learning curves that might turn teams off from developing with React/JSX in the long-term.

Related reading: Vue.js vs. Angular in 2021: Side-by-Side Comparison

Is React Used in Frontend or Backend Development?

Although React has inherent features and capabilities that are made possible by backend development (as for any JavaScript library), it exists primarily as a front-end library/framework. All components and elements of React/JSX are centered on UI design components based on JavaScript.

More importantly, with its use of Virtual DOM to update UI components and elements, it distinguishes itself as a frontend leader as it simply needs UI data to input and updates its virtual DOM tree.

How Popular Is React Nowadays?

As a distinguished and open source leader in sleek, cross-platform UI design interfaces, the React library has gained incomparable traction in the previous 8-9 years.

ReactJS has emerged as one of the most popular JS libraries due, with an estimated 1,300 developers and over 94,000 sites utilizing ReactJS.

Additionally, React takes the cake as the highest percentage of users who would use a framework again.

React expectedly comes in first place at 92% of users who would reuse the framework with Vue trailing behind at 88% and Angular2 at ~64%.

Related reading:  Vue.js vs. React: Which Is Better?

What is React Used For?

Excluding widely-known React-adopted mobile and web applications like Facebook and Instagram, ReactJS has dominated the landscape of mobile and web app development in top Fortune 500 companies.

For example, Asana, a project management tool, is a web and mobile application designed to effectively help teams organize, track, and manage their work.

Additionally, companies such as Khan Academy, a leading online learning non-profit across every spectrum of subjects, Codecademy, Yahoo! Mail, the New York Times, and PayPal actively employ react in their UIs.


As the critical demand for more sleek, optimized, efficient, and modular User Interfaces increases in the next several years, having an all-in-one library that can manage the frontend state of your mobile and web applications is crucial.

Whether you’re using JSX to create a responsive, leading web application, or React Native to deploy cross-platform mobile applications on Android and iOS, React offers the absolute best of both worlds.

However, getting your hands on developers with a substantial grasp of JS libraries and frameworks has become increasingly difficult as talented development teams are constantly eaten up by the second.

Consider outsourcing to companies like Trio to hire React developers for your next big project.

Trio’s team of fresh and upcoming React developers are willing to work with startups and businesses, large and small, to develop and release fully responsive mobile and web applications.

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With over 10 years of experience in software outsourcing, Alex has assisted in building high-performance teams before co-founding Trio with his partner Daniel. Today he enjoys helping people hire the best software developers from Latin America and writing great content on how to do that!
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