1. What is React?

React is a popular JavaScript library developed by Meta (Facebook) for building user interfaces, especially single-page applications (SPAs).

• Component-based architecture
• Virtual DOM support
• Reusable UI components
• Fast rendering performance

2. What is Virtual DOM in React?

The Virtual DOM is a lightweight copy of the real DOM. React updates the Virtual DOM first and compares it with the previous version using reconciliation.

React updates only the changed elements in the real DOM, improving performance significantly.

3. What are Components in React?

Components are reusable building blocks in React applications. They help developers create modular and maintainable UI structures.

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

      

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4. What is JSX?

JSX stands for JavaScript XML. It allows developers to write HTML-like syntax inside JavaScript.

const element = <h1>Welcome to React</h1>;

      

5. What are Props in React?

Props are used to pass data from parent components to child components.

function User(props) {
  return <h1>Hello, {props.name}</h1>;
}

<User name="Bhim" />

      

6. What is State in React?

State is used to manage dynamic data inside React components. Whenever state changes, React re-renders the UI automatically.

const [count, setCount] = useState(0);

      

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Final Thoughts

React interviews in 2026 focus heavily on hooks, component architecture, performance optimization, state management, and real-world frontend problem solving.

Practice consistently, build projects, and stay updated with the latest React ecosystem trends to become a successful frontend developer.