React Tutorial (original) (raw)

Last Updated : 18 Apr, 2025

React is a **JavaScript Library known for front-end development (or user interface). It is popular due to its **component-based architecture, Single Page Applications (SPAs), and Virtual DOM for building web applications that are fast, efficient, and scalable.

• Applications are built using reusable components that enable the reload of only the changed part of the UI. Hence we get a better user experience with React.
• Allows you to describe how the UI should look based on the state of your application.
• Uses a virtual DOM to optimize updates, making applications faster and more efficient.
• Enforces a one-way data flow, making the application predictable and easier to debug.
• It uses JSX, which combines HTML-like syntax with JavaScript's functionality, making it easy to shift to React from JavaScript.

**Note: The latest stable version of React is 19.1.0.

React Hello World Program

To start with React, you need to install it. Follow the steps below to install it on your system.

1. How to Install ReactJS on Windows
2. How to Install ReactJS on MacOS
3. How to Install ReactJS on Linux

After installing React, let's write your first React program. Here's a simple code example:

JavaScript `

import React from 'react';

function App() { return (

export default App;

`

**In this example:

• **import React from 'react': Imports the React library to use React features in the component.
• **function App() { ... }: Defines a React functional component called App.
• **return ( ... ): The return statement renders HTML-like code (JSX) inside the component.
• ****

  Hello World

  **: Displays a div element containing a heading (h1) with the text "Hello World."
• **export default App: Exports the App component so it can be used in other files.

**Why Learn React?

React, the popular JavaScript library, offers several exciting reasons for developers to learn it.

• **Flexibility: React allows you to build high-quality user interfaces across different platforms, thanks to its flexible library approach.
• **Great Developer Experience: React makes it easier to write and understand code, offering a smooth development process.
• **Strong Support from Facebook: Regular updates, bug fixes, and resources from Facebook ensure React stays up-to-date and reliable.
• **Vast Community Support: React benefits from a large community, providing enough resources, tutorials, and troubleshooting help.
• **Excellent Performance: React’s efficient Virtual DOM ensures fast rendering and high performance for web applications.
• **Easy Testing: React’s structure and tools make testing simpler, improving code reliability and maintainability.

**React Tutorial Prerequisites: HTML, CSS and JavaScript

Getting Started with React: A Beginner’s Guide

This React tutorial provides you with a step-by-step learning journey for mastering php. You will start with React fundamentals and then move on to advanced topics. By the end of this tutorial, you will have a solid foundation in React and be ready to build scalable and maintainable web applications.

1. React Basics

• Introduction
• Import and Export
• JSX Introduction
• Components
• Conditional Rendering
• Virtual DOM
• PropTypes
• Prop Drilling
• React Lists
• Context API
• React Redux

2. React Hooks

Different hooks to access and mange state and lifecycle in functional components.

• Hooks Introduction
• useState Hook
• useEffect Hook
• useRef Hook
• useMemo Hook
• useContext Hook

**3. React DOM Events

Handle DOM events in react like mouse, keyboard and form events.

• React Events Introduction
• onclickcapture Event
• onMouseDown Event
• onDoubleClick Event
• onSubmit Event
• onScroll Event
• onBlur Event

**4. Lifecycle of Components

The lifecycle of react components from creation, mounting and unmounting to manage the different phases.

• Introduction to lifecycle of components
• componentDidMount
• componentWillUnmount
• componentDidCatch
• componentDidUpdate
• shouldComponentUpdate

5. Routing in React

Manage navigation and routing within the single page application.

• React JS Router
• What is react-router-dom?
• React JS Types of Routers
• React-Router Hooks
• Learn Navigation and Routing in React Apps
• Link and NavLink components in React-Router-Dom

6. Important React Packages

Additional libraries for styling and state management to enhance your react projects.

• Redux
• Material UI
• react-bootstrap
• Tailwind
• Framer Motion

7. React Interview Questions

React Interview questions categorised for different levels including most asked questions.

• Beginner Level Interview Questions (2024)
• Intermediate Level Interview Questions (2024)
• Advanced Level Interview Questions (2024)
• 7 Most Asked ReactJS Interview Questions

8. React Online Quizs

Test and Improve your knowledge with the well organised React Quizs

• Set-1
• Set-2
• Set-3
• Set-4
• Set-5
• Set-6

9. React Online Practice Exercise

Embark on your React learning journey with our online practice portal. Start by selecting quizzes tailored to your skill level. Engage in hands-on coding exercises, receive real-time feedback, and monitor your progress. With our user-friendly platform, mastering React becomes an enjoyable and personalized experience.

Elevate your coding expertise by going through our carefully curated Free Online React Exercises.

10. React Complete References

Refer to the following articles to have a quick glance at all the important key concepts which are helpful while developing web applications using React

• Basic Concepts Reference
• Components Complete Reference
• Props Reference
• Events Reference
• Hooks Reference
• Advanced Guide Reference

If you want to have a simple, quick reference to commonly used React methods you can refer to ReactJS Cheat Sheet article

**Advantages of React

• **Composable: React allows building reusable components, improving code organization and maintainability.
• **Declarative: React’s declarative approach makes it easy to design interactive UIs by changing component states, with React handling the DOM updates.
• **SEO-Friendly: React’s Single Page Application (SPA) setup can be optimized for SEO by rendering and indexing content properly.
• **Large Community: React has a strong community and is widely used by major companies like Meta, Netflix, making it easier to find resources and support.
• **Easy to Learn: React uses JSX, which resembles HTML, making it simple for developers with basic knowledge of HTML, CSS, and JavaScript.
• **Easy Debugging: React’s unidirectional data flow simplifies debugging by ensuring that data moves in a clear, predictable direction within components.

If you want to learn more refer to this article React JS Advantages

Best Approach to Learn React

You can complete this React tutorial in approximately 8 weeks with consistent learning and hands-on practice.

• In Week 1, you'll cover React basics, including components, JSX syntax, and topics like conditional rendering, prop-types, React lists, and React Redux for state management.
• Week 2 focuses on React Hooks, where you'll learn about useState, useEffect, useRef, and useContext for state management and performance optimization in functional components.
• In Week 3, you’ll learn how to handle DOM events like clicks, keyboard input, and form submissions in React.
• Week 4 dives into the lifecycle of components, explaining lifecycle methods in class components and their equivalent in functional components using hooks.
• Week 5 will teach you React Routing with react-router-dom, managing navigation and routes in single-page applications.
• In Week 6, you'll explore important React packages like Redux, Material UI, React-Bootstrap, Tailwind, and Framer Motion for styling and animations.
• Week 7 covers React interview questions for different levels, helping you prepare for job interviews.
• In Week 8, you'll apply everything you've learned by building real-world React projects, consolidating your knowledge.

By the end of 8 weeks, you’ll be proficient in React and ready to build dynamic web applications.

React vs Angular

Below is the difference between the React and Angular.

List of Companies Using React

These are some popular companies that use React in their workflow:

Career & Jobs in React

React offers a wide range of career opportunities, as it is one of the most popular front-end libraries used in web development, particularly for building dynamic and responsive user interfaces. React is widely adopted for both web and mobile applications, making it a highly sought-after skill in the industry. Here are some top career paths for React developers: