What is React? History & Key Features

React is an open-source JavaScript library used for building user interfaces (UIs), especially single-page applications (SPAs). Developed by Facebook (now Meta), React allows developers to build fast, interactive, and reusable UI components for web and mobile apps.

Unlike traditional page reloads, React updates only the parts of the page that change. This makes web applications faster, smoother, and more efficient.

Think of React as LEGO blocks – you can build small reusable pieces (components) and then combine them to make large applications.

A Brief History of React

React didn’t appear overnight. Let’s go step by step:

  • 2011 – Facebook engineer Jordan Walke created React to solve performance issues in Facebook’s news feed.

  • 2012 – React was first used in Instagram’s web application.

  • 2013 – React was officially open-sourced by Facebook at JSConf US.

  • 2015 – React Native was launched, enabling mobile app development for iOS & Android using React concepts.

  • Today – React is maintained by Meta and a large community, powering popular apps like Netflix, WhatsApp, Airbnb, and Instagram.

Key Features of React

Here are the features that make React so powerful and popular:

  1. Component-Based Architecture

    • Apps are divided into small, reusable components (like buttons, forms, navigation bars).

    • Each component handles its own logic and UI, making development easier and faster.

  2. Virtual DOM (Document Object Model)

    • React uses a virtual copy of the DOM to quickly update changes.

    • Instead of reloading the whole page, only the updated parts are changed, boosting performance.

  3. One-Way Data Binding

    • Data flows in a single direction (parent → child).

    • This makes debugging and data management more predictable.

  4. JSX (JavaScript XML)

    • A syntax extension that lets you write HTML-like code inside JavaScript.

Example:

 
const element = <h1>Hello, React!</h1>;

    • This makes code more readable and easier to maintain.

  2. React Hooks

    • Introduced in React 16.8, Hooks let you use state and lifecycle features in functional components.

    • Example: useState, useEffect.

  3. Cross-Platform with React Native

    • Write once, use across web and mobile apps.

  4. Strong Community & Ecosystem

    • Backed by Meta and millions of developers worldwide.

    • Huge library ecosystem for routing, state management, testing, etc.

Why Use React? (Benefits)

  • Fast Rendering with Virtual DOM

  • Reusable Components save development time

  • SEO-Friendly (with server-side rendering)

  • Huge Community Support

  • Future-Proof: Used by top companies worldwide

Example – A Simple React Component

function Welcome() {
  return <h1>Hello, React Learner!</h1>;
}

This small component displays a simple greeting. In a real app, you combine such components to build full features.

FAQ – Frequently Asked Questions

Q1: Is React a library or a framework?
 React is a JavaScript library, not a full framework. It focuses only on building UIs.

Q2: Do I need to know JavaScript before learning React?
 Yes. Strong basics in JavaScript, HTML, and CSS are essential before diving into React.

Q3: Is React still popular in 2025?
Absolutely. React remains one of the most used JavaScript libraries worldwide, powering startups and enterprise apps alike.