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Hari Om Singh
Hari Om Singh

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How React Works!

React Background and History

React.js, commonly referred to as React, is a JavaScript library for building user interfaces, particularly single-page applications where smooth and responsive user experiences are essential. React was created by Jordan Walke, a software engineer at Facebook, and was initially deployed on Facebook's newsfeed in 2011. Its primary purpose was to address certain challenges and improve the efficiency of building complex, dynamic user interfaces.

Traditional web development involves frequent updates to the Document Object Model (DOM), which can be computationally expensive and can lead to suboptimal performance, especially when dealing with complex, data-rich applications. React introduced a virtual DOM, a lightweight copy of the actual DOM, to efficiently update only the necessary parts of the UI, minimizing unnecessary re-rendering and improving performance.

React promotes a component-based architecture, allowing developers to create reusable and modular components. Components encapsulate specific functionality, making it easier to manage, update, and reuse code. This approach enhances development speed and maintainability by facilitating the composition of complex interfaces from simpler, smaller components.

Which Problem does React Solve by itself

As I said earlier traditional web development involves lots of change when it comes to rendering something or showing dynamic content, Which can be very expensive and not very effective, That is Where React comes with the solution of SPA (Single page rendering)

React introduced a virtual DOM, a lightweight copy of the actual DOM, to speed up the rendering and it only changes the necessary part of the UI

React promotes a component-based architecture, allowing developers to create reusable and modular components. Components encapsulate specific functionality, making it easier to manage, update, and reuse code

React enables a declarative approach to building user interfaces. Developers can describe what the UI should look like based on the application state, and React handles the updates to reflect changes in the state.

React promotes a unidirectional data flow, which helps in maintaining a predictable and traceable state within the application

Virtual Dom

The Virtual DOM is a key concept in React.js that significantly contributes to its performance and efficiency. It's a lightweight, in-memory representation of the actual DOM (Document Object Model), and React uses it to determine the minimum number of updates needed to keep the UI in sync with the application state.

React builds a representation of the browser Document Object Model or DOM in memory called the virtual DOM. As components are updated, React checks to see if the componentโ€™s HTML code in the virtual DOM matches the browser DOM. If a change is required, the browser DOM is updated. If nothing has changed, then no update is performed.

As you know, this is called the reconciliation.

By utilizing the Virtual DOM and performing the diffing process, React minimizes the number of updates to the real DOM, reducing the overall computational effort and enhancing application performance. This approach significantly contributes to React's reputation for providing a responsive and efficient user interface, even in complex and dynamic web applications

By employing these principles and techniques, React enables efficient UI rendering, encourages a modular and reusable code structure, and helps manage complex UIs with ease, making it a popular choice for building modern web applications.

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