React Syllabus

React is one of the most popular JavaScript libraries for building user interfaces, especially single-page applications. Developed and maintained by Facebook, it’s known for its speed, flexibility, and scalability. Whether you’re a beginner starting your frontend journey or a developer wanting to master component-based architecture, React is an essential skill in modern web development.

This guide provides a comprehensive syllabus of React covering all the important topics—structured from beginner to advanced—ideal for self-learners, students, and developers.

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1. Introduction to React

• What is React?
  • React is a JavaScript library for building fast and interactive UIs.
  • It allows developers to build reusable components.
• Why React?
  • Virtual DOM
  • Component-based structure
  • Huge community support
  • Used by major companies like Facebook, Instagram, Netflix
• React vs Angular vs Vue
  • Comparisons on architecture, learning curve, performance

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2. React Setup & Environment

• Installing Node.js and npm
  • React apps need Node and npm to manage packages.
• Create React App (CRA)
  • Using npx create-react-app to quickly scaffold a new project.
• Understanding Project Structure
  • public/, src/, App.js, index.js, package.json
• Running the development server
  • Using npm start to preview the app locally.

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3. JSX (JavaScript XML)

• What is JSX?
  • Syntax extension that looks like HTML in JavaScript.
• Why use JSX?
  • It helps to write readable UI code and integrates JS logic easily.
• JSX Rules
  • One root element
  • Self-closing tags
  • Use className instead of class
  • Curly braces for JS expressions

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4. Components in React

• What are Components?
  • Reusable building blocks for UI
• Types of Components:
  • Functional Components (modern standard)
  • Class Components (older approach)
• Creating Components
  • File naming conventions
  • Exporting and importing components
• Props in Components
  • Passing data from parent to child using props
  • props.children concept

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5. State Management

• What is State?
  • An object that determines the component’s behavior and rendering.
• Using useState Hook
  • Declaring and updating state in functional components.

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

• Event Handling in React
  • onClick, onChange, onSubmit
  • Binding event handlers

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6. React Lifecycle (for Class Components)

• Lifecycle Methods:
  • constructor()
  • componentDidMount()
  • componentDidUpdate()
  • componentWillUnmount()
• useEffect Hook (Functional Lifecycle)
  • Side effects like API calls, timers, event listeners

useEffect(() => {
  // effect code here
}, []);

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7. Conditional Rendering

• Using if-else inside JSX
• Ternary operator
• Logical && operator

{isLoggedIn ? <Dashboard /> : <Login />}

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8. Lists and Keys

• Rendering Lists
  • Using .map() to display arrays
• Keys in React
  • Importance of unique keys for elements in a list

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9. Forms and Form Handling

• Handling form inputs
  • Controlled components using useState
• Handling submit
  • Preventing default and accessing form data
• Form Validation (Basic)
  • Using conditionals and error states

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10. React Hooks (Modern React)

Hooks let you use state and lifecycle methods in functional components.

• Basic Hooks:
  • useState – for local state
  • useEffect – for side effects
  • useRef – for DOM references
• Advanced Hooks:
  • useContext – for global state
  • useReducer – for complex state logic
  • useMemo, useCallback – performance optimization
  • useLayoutEffect, useImperativeHandle

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11. React Routing (React Router)

• Installing React Router
  • npm install react-router-dom
• Basic Routing
  • Using <BrowserRouter>, <Routes>, and <Route>
• Route Parameters
  • Dynamic routing with :id
• Navigation
  • Using Link, NavLink, and useNavigate

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12. State Management with Context API

• What is Context?
  • Provides a way to pass data through the component tree without props.
• Creating Context
  • React.createContext()
• Using Provider and Consumer
  • Wrap components in context and access shared data

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13. Fetching Data from APIs

• Using fetch() or axios
• Display data using useEffect
• Loading and Error handling
• Async/Await in useEffect

 useEffect(() => {
  const fetchData = async () => {
    const res = await fetch('https://api.example.com/data');
    const data = await res.json();
    setData(data);
  };
  fetchData();
}, []);

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14. Styling in React

• CSS Stylesheets
• Inline styles
• CSS Modules
• Styled-components (optional library)
• SASS with React

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15. React Developer Tools

• Chrome DevTools Extension for React
• Inspect component tree and props/state

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16. Custom Hooks

• Creating your own hook
  • Functions that start with use
• Reuse logic across components

function useCounter(initialValue) {
  const [count, setCount] = useState(initialValue);
  const increment = () => setCount(prev => prev + 1);
  return { count, increment };
}

17. Code Splitting and Lazy Loading

• React.lazy and Suspense
  • Load components only when needed to improve performance

const LazyComponent = React.lazy(() => import('./LazyComponent'));

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18. Testing in React

• Using Jest and React Testing Library
  • Unit tests for components
  • Snapshot testing
  • Mocking functions and events

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19. Deployment

• Build the project
  • npm run build
• Deploy on:
  • GitHub Pages
  • Vercel
  • Netlify
  • Firebase Hosting

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20. Bonus Topics (Advanced)

• Higher Order Components (HOC)
• Render Props
• Portals
• Error Boundaries
• SSR with Next.js
• React Native (for mobile apps)

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Conclusion

Learning React is not just about understanding components—it’s about mastering how to think in a component-driven, declarative style. The above syllabus gives you a clear roadmap from beginner to advanced level. Whether you’re building personal projects or applying for jobs, this structure ensures you cover everything from basics to deployment.