What is ReactJS

ReactJS is one of the most preferred Javascript libraries which is used by developers to create dynamic and robust UI (User Interfaces) for the web. It was developed by Facebook in the year 2013. ReactJS has a market share of approx 42.62% which makes it one of the market leaders across the globe. The demand for ReactJS has been growing exponentially lately, it is now the most popular framework for front-end development. ReactJS has emerged as the most promising technology for the future of the web because of its versatility and simplicity. Bloomberg, Salesforce, Discord, Uber eats and others are some of the tech companies leveraging ReactJS technology for its growth and development.

What is ReactJS?

React is an in demand Javascript library which is used for web development. React, React.js or ReactJS are some of the names it is popularly known as. React is responsible for developing the application’s view layer since the framework is component-based. It is also an open-source platform. It follows MVC (Model View Controller) architecture, and for handling the web apps and mobile apps the view layer of React.JS is accountable.  It is used worldwide mostly for building mobile applications and single-page apps. 

            React divides the user Interface into various components so that the code becomes easy for debugging. This helps to assign a specific component to each function and it then produces HTML that is rendered as the output by Document Object Model (DOM). It is considered to be one of the best frameworks in Javascript and plays a vital role in the front-end ecosystem.

Why ReactJS?

There are numerous reasons for choosing ReactJS as the primary tool for building applications. ReactJS gives a lot of flexibility to its users. You can develop SPAs, TV applications, mobile, hybrid applications, and others using ReactJS.  If you are looking to build a hugely complex web application, you can also add external tools and libraries if required in ReactJS. It will make sure that the performance of the application built is optimised. It permits the user to write smaller and reusable files alternatively to writing huge, dense files. The learning arc for React is low because a minimal understanding of HTML and javascript is required. 

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Brief History of ReactJS

ReactJs was created by a software engineer named Jordan Walker at Facebook. A prototype known as “FaxJS'' was released in the early stages by him. XHF and HTML  which are the component libraries for PHF influenced him to create React. As it was created by Facebook it was first deployed in the year 2011 in the News feed of the company and later in the year 2012 for Instagram.  In the year 2013, it was then open-sourced to the public at JSConf US.

Building Components of React

1. React Js Components:

Components allow the user to split the user interface into independent and reusable sections. Each section can then be looked at as an isolated part for further evaluation. Therefore components are referred to as the heart and soul of ReactJs. Each component has its method, structure, and API. They are the building blocks of every React application. The components in React are divided into two parts which are as follows-

  • Class components: These components are complex as compared to functional components. They can return to Javascript XML on the screen and also have a discrete render method to govern their state.
  • Functional components: These components are different from class components. They do not have their state and have a render method only.  In other words, they are simple javascript functions that might or might not receive the data as specified. 
2. React state:

A state is referred to the place from where the data comes in. In a component, the state can change anytime, and whenever it modifies, the component will re-render. Changes could be a result of various actions such as system-generated events or even user actions and these changes then define the behaviour of the component and how it will be rendered. The constructor initialises the object of a state. Multiple properties can also be stored in it.  Use the setState() function to change the value of the state object. Also, you can use the setState() function so that the new and previous states can be merged.

3. React Props: 

Props, known as “ Properties’ are Read-only components. State and Props are simple javascript objects. These components hold the data which influences the output of render.  Both State and Prop are different from one another, one is managed inside the component in a similar way a variable is declared in a function and the other is passed to a component such as the function parameters respectively.

4. React keys:

A key is used only while working with dynamic components that are created. If the user sets the key value it helps to keep the component unique even after any modification. A user helps React identify all the items that are changed, added, or removed.

In a nutshell, you will have to be familiar with all the components before you begin your journey with React!

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Important Features of ReactJS:

Following are the essential features of ReactJS

1. Simplicity:

ReactJS uses the Javascript XML file (JSX) that helps in executing the application easily. This also simplifies the understanding of the code. The approach of ReactJS is component-based; it will always be able to reuse the code whenever required. This makes it even more simple and easy to learn. 

2. Virtual DOM:

Virtual  DOM (Document Object Model) is a description of the original model. It is a one-way process of data binding. If there are any modifications in the web application, the complete User Interface is re-rendered in the representation of virtual DOM. It will always compare the new and the previous DOM to find the difference between the representation. After the comparison is completed the original DOM will update the modified changes. The application’s memory will not be wasted anymore and it will be able to run fast.

3. JSX- Javascript syntax Extension:

ISX refers to the Javascript SyntaxExtension. It is either XML or HTML syntax which ReactJS uses. The framework of React is implemented into the Javascript calls using the syntax. The file that has the Javascript code and HTML structure is also written in the same file using JSX. This helps to understand and debug the code easily. It can also help in avoiding the DOM structure of Javascript which is complicated.

4. Performance: 

ReactJS performs effectively and efficiently. It operates faster than other alternative options for front-end frameworks in the market. It divides the UI which is complex into many unique elements. To increase productivity and decrease the time of development, many users can work together on each element parallelly.

5. One-way Data Binding:

ReactJS is designed in a way it can support Unidirectional data flow or One-way binding.  The biggest advantage of this feature is it provides control to the user all around the application.  Sometimes the data flows in another direction, that is the time it requires additional features. Since the components should remain permanent and also the data which is inside should not be modified. In such cases, most of the developers use Flux, a programming language to support the data flow in a unidirectional process. This will help the applications to increase their efficiency and also be more flexible.

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ReactJs Advantages

ReactJs has numerous advantages that are as follows;

  • ReactJs helps the user to create amazing UI for applications.
  • It can also be used with alternative frameworks that are available in the market.
  • It is SEO-friendly too. 
  • It facilitates an increase in productivity along with advanced maintenance.
  • It has its own DOM, which helps in improving the performance since the regular DOM is slower as compared to the javascript DOM.
  • It helps in faster rendering.
  • ReactJS is easy to learn and implement as it comes with a developer toolset.
  • Scripting environment processes get simplified easily with the help of ReactJS.

Hope you now understand the concept of ReactJs along with its features and advantages. The chief objective of using ReactJS is its potential to use the components repeatedly. Easy to learn and simple to implement hence preferred by most organizations across the globe for the development of their applications. A recent study by Statista indicates that ReactJS is among the most in-demand web frameworks in 2022. As technology progresses so do the opportunities. Explore all the career options by visiting HKR training. Let us know if you have any queries via the comment section.

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As a content writer at HKR trainings, I deliver content on various technologies. I hold my graduation degree in Information technology. I am passionate about helping people understand technology-related content through my easily digestible content. My writings include Data Science, Machine Learning, Artificial Intelligence, Python, Salesforce, Servicenow and etc.

It is an open-source, front-end library based on components, responsible for the view layer in the application.

ReactJs is used to write HTML using Javascript. Therefore the user will have to depend on Javascript to generate HTML.

React is an efficient, flexible, and declarative Javascript library that is used for building User Interfaces for applications.

React JS uses Javascript to build applications.

ReactJs helps in maintaining larger applications by improving the readability of Data patterns and components.

ReactJs is used to build websites using its library whereas HTML (Hypertext Markup Language) is used to structure the websites. 

The primary advantage of using ReactJS is that it helps its users to re-use the components which saves time and the developers don't have to write the same code again for the same features.