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ReactJS Introduction

React Tutorial helps you to understand the basic and some advanced concepts of ReactJS. As of now, it is the essential front-end library that is developed by a software engineer name Jordan Walke in facebook. It has a strong foundation with a large community.

Facebook was the first that has developed and maintained it, and after that, used in its products like WhatsApp and Instagram. Facebook was the first that established the React in 2011, but it was presented to the public in May 2013.

Now, many websites are based on MVC (Model View Controller) architecture. According to MVC, React is the ‘V’ which stands for View.

There are several components to build the ReactJS application; these components act as the heart of all of the React applications. When these components are added to other elements, then together, they will allow creating complex applications. It uses virtual DOM to fill the data in the HTML DOM. Virtual DOM is fast because there is a need to change only in the components of individual DOM instead of reloading the complete DOM.

For creating the React applications, we require React components; these components will further be organized inside the higher-level elements that together define the application structure.

Let’s understand it with an example like a form that includes buttons, labels, and input fields. We can tell each element of the form is the React components, and form itself is the higher-level component that together defines the form’s structure.

Why ReactJS?

Many JavaScript frameworks are already available in the market like angular, node, but still, JavaScript is more popular among them. There is a reason behind it, that the old frameworks follow the structure of traditional data flow, and uses the DOM (Document object model). DOM is nothing but an object each time created by the browser whenever a web page is loaded.

Whenever any modification is done in the backend, DOM can add or removes the data from the backend; and at the same time, a new DOM is created on the same page. This unnecessary wastage of memory and DOM’s repeated creation reduces the application of the performance.

So, for removing this drawback, the technology ReactJS framework invented, which allows the partition of the entire application into several components. ReactJS also uses the traditional data flow and operates on the virtual DOM, but not directly operates on the browser’s DOM. Due to this mechanism, we don’t need to manipulate the whole document; the changes resolve on the DOM, which is run in the memory.

After the updating of Virtual DOM, React determines the amendment that requires in the actual browser’s DOM. Because of this, we have to write virtual components that React will turn into the real DOM instead of writing a React component directly into the DOM.

ReactJS Index

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