Reactjs Overview

What is Reactjs?

ReactJS is the most popular open-source Javascript library that is used for developing interfaces. This web framework is used for designing spectacular interfaces for web and mobile apps, especially for Single Page Applications. ReactJS is only used for creating the front end, and it does the job very proficiently.

How does ReactJS Work?

ReactJS updates the overview of the application when a change is made in the data or state. For this, ReactJS uses virtual DOM instead of continually updating Real DOM. This makes the working of React very fast. When a component is created in React, then it creates its virtual DOM, which is the Javascript representation of the DOM.

As soon as a change is made in the component, ReactJS updates the virtual DOM. And it instantly changes the component in the UI of the application. React only updates the parts that have been altered in the program code instead of updating the entire web page.

ReactJS History

Jordan Walke, a software engineer, working on Facebook, at first created “FaxJS.” It was the prototype of the framework that is currently known as ReactJS. In 2011, FaceBook adopted React because Ads management was becoming quite difficult. And later Instagram wanted to use React, so in 2012 Instagram took React.

In May 2013, react went open source at JSconf. In the initial years, react was ignored as it was considered as a backward technology. In 2014, React became available on several applications like Python. From there, React went in demand, and it created its reputation in the market. After this, react was adopted by several companies, and it developed a potential user base.

Reactjs Features

Component derived Programming:

ReactJS incorporates components-based programming. These small entities can have certain logic and can be rendered in the DOM. These components are reusable, and they can manage their state. This architecture is beneficial when the applications are vast. These components are not in the scope of the DOM, and hence an exceptional data can be passed from the components. Also, these components can be used in other frameworks like Angular.


JSX is the most preferred Syntax use to write codes in React. It is the most efficient and most straightforward language to design react apps. It is a combined language of Javascript and HTML. It provides a familiar developing environment for developers as it closely resembles HTML. Thus, a beginner developer can also understand and write ReactJS applications.

Virtual DOM:

Virtual DOM management is the most exceptional feature adapted by ReactJS. It enables rapid reloading and saves the time of the developer by refreshing the page every time a change is made. It is the virtual representation of the Browser’s DOM written in Javascript language. ReactJS compares the old and new Virtual DOM and makes changes in those components in the interface that have been changed. This avoids the excessive use of resources of the device.

Declarative Programming:

With declarative programming, there is no need to refresh the page. A change made in the program is automatically updated on the web page. Also, the declarative feature is built to code less and create more. In react, you only need to specify the utility you want to use, and React will implement it. The major advantage is that you don’t need to specify How things are to be done; you only need to tell what has to be done. React will perform the task on its own.

React Hooks:

React offers the feature to use Hooks outside a class. This lets the developer access the functions without defining a class. useState, useContext, useReducer, and useEffect are a few examples of the built-in React Hooks. These hooks make the code much easier to understand and read. While implementing, there are specific protocols that have to be followed for writing the syntax.

React also allows you to design custom hooks that can have your own login. These hooks can also be used multiple times.

One-way Data flow:

ReactJS features a one-way data flow that increases the efficiency of the App. The components in React are immutable and cannot be changed with the two-way data flow. Hence it follows one-way data binding that requires fewer resources. React utilizes the Flux pattern to manage the unidirectional flow of data within the project. One-way data flow gives a developer a much convenient way to handle and control the application.


ReactJS uses JSX (JavaScript XML), which is very straightforward to write and understand. It offers the capabilities of HTML language and access to a vast number of HTML attributes. The file management in ReactJS is very simplified, which makes the location very effortless. Relocation of previously created projects becomes convenient because of the utilization of ReactJS


Quick learning:

ReactJS is very convenient to learn as it does not require in-depth knowledge of Javascript. Whereas, in other frameworks like Angular and ember, you will need to have significant experience of a specific Programming language. You can create highly interactive User Interfaces with the basic knowledge of Javascript and CSS.

Reusable components:

The components created in the program can be reused whenever required. Not only in the same application, the components can be transferred to other projects and used there also. Code reusability reduces the time for developing the App.

While creating updates, the developer does not need to create components again. Each component can be updated separately, and this does not affect other components. This gives greater flexibility and precise programming for developers.


With the use of templates, the coding length is significantly reduced. Templates can be found in React Tools, and These tools include a vast library of templates. You can include the templates in your application quickly and start rebuilding the App. Also, these predesigned components are totally customizable; you can change every component of the template.

By using a template, you can build an excellent interface instead of starting from scrap.  

React is open source:

ReactJS is the first open-source Javascript library that was released by Facebook. This means the vast library is continuously upgrading and becoming more efficient day by day. Besides, ReactJS has access to several additional tools and assets of other companies for free.

As it is open-source, any developer can share its project over GitHub. Also, you can access useful projects shared by other developers on GitHub. An interesting fact is that react is the 5th trending topic in GitHub.

React Native for mobile Apps:

ReactJS has a platform for the development of native mobile apps called React Native. It is entirely similar to ReactJS, facilitating the same programming approach and all the functions. All the features like Virtual Dom management, components, etc. are included in React native as well.

React native does not require any specific language; it uses the same JSX language. Hence, a developer can create interfaces for both IOS and android with outstanding performance.

SEO friendly:

Almost every search engine finds rendering the Javascript app difficult this often leads to failures. ReactJS counters this problem by server-side rendering and pre-rendering. Server-side rendering allows the browser to access all the content and HTML files quickly and rank your page higher during searches.

ReactJS tools offer several ways to make your app SEO friendly. You can use them to make sure that your protocol ranks much higher than others.

Quick rendering:

When you are creating large applications with complex coding, there is a chance that the software you are using may lag somewhere. ReactJS is the most optimal tool for rendering. ReactJS, with the help of Virtual DOM, manages the rendering simultaneously as you are coding.

It renders the code as soon as it is written, and whenever a new component is written, it automatically renders only the new part.


Complete focus on UI:

ReactJS is made explicitly for developing the interface of the application. Thus, it has no control and capability to create the back end of the application. This puts the point that ReactJS is not a complete tool for full-stack development. You will need to integrate the software and tools for designing the back end of the App. Because of this, some developers see React as a narrowly focused framework for development.

Imperfect Documentation:

Documentation is another flaw in ReactJS. As the React library is improving and updating rapidly, the developers have no scope to take proper documentation. Thus, the libraries integrated into ReactJS are also lacking in documentation. Because of this, developers tend to write the documentation on their own after new releases.

This leads other developers not to get familiarized with the new features and updates. While creating the App, the developers find it difficult to note down every change because of fast reloading.

Problem with JSX:

JSX makes the program more readable and simpler to understand. Also, JSX is responsible for efficient DOM manipulation, but it has its own drawbacks. Beginner developers get confused while learning JSX. In the initial stage of learning, React developers are more comfortable with HTML or Javascript. But a combined language of JSX often creates confusion for them. Hence new developers treat JSX as a barrier in their learning procedure.

The fast pace of Growth:

ReactJS is growing rapidly in the development community. This has good advantages as well as certain drawbacks. With the constant improvements in the programming environment, some developers face difficulties while adapting to new technologies and foundations. Some updates change the interface and the process of executing a task. New developers find it challenging to keep up with the updates and adapt to new ways of doing the same job.  

Complicated SEO optimization:

Optimizing your App according to the standards of the Search engine, can be a very complicated task. Google uses Bots for ranking pages while searches are done. These Bots index HTML pages quickly, and Javascript designed pages are ranked lower. To compensate, this React has a complex procedure of optimization through JSX. Thus, optimizing may lead to more complicated tasks as it takes time to load the page. If it is not optimized correctly, google bots leave the page, and it is not listed among the tops.

Need other libraries:

Since ReactJS is a framework, it requires several other libraries to be included. For the addition of unique functionalities, React needs some libraries that need to be downloaded. To create an App in Create react App, you will need to install npm or yarn libraries accordingly. Similarly, if you are using the Bootstrap framework, you will need to download it and its dependencies for using it.

Selecting a tool:

Because of the popularity of ReactJS, there are several tools in the market for building react applications. Thus, for a developer selecting a tool becomes frustrating. These tools have specific features, and no tool is capable of being used as a full-scale developer. Rectide, React Sight, Storybook, CodeSandbox, React Developers Tools, Bit are some of the react tools. Each of these tools can perform exceptionally in a particular thing. Hence, finding a perfect tool can become a major disadvantage of ReactJS.  

Final verdict:

ReactJS can be used for creating exceptional and dynamic interfaces. It provides a comfortable and effortless development of applications. It has several advantages over other tools like components, Virtual DOM, reusability, etc. At the same time, these advantages can act as a barrier to new developers. Since adapting to these features can take noteworthy time to learn. But overall, ReactJS can improve the performance of development remarkably.