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Getting Started with React - Create your first app

Kaajoo Admin
Kaajoo Admin How to

React is a popular JavaScript library for building user interfaces, and it's widely used for developing modern, single-page applications. Here's a step-by-step guide to help you get started with React:

1. Set Up Your Development Environment:

Node.js and npm:

Ensure you have Node.js installed on your machine. npm (Node Package Manager) comes with Node.js.

Create React App:

You can use Create React App, a tool that sets up a new React project with a good default configuration. Open your terminal and run:

npx create-react-app my-react-app

Replace "my-react-app" with the name you prefer for your project.

2. Project Structure:

Navigate into your project directory:

cd my-react-app

Explore the project structure. The main files you'll work with are located in the src folder.

3. Understanding Components:

React is based on the concept of components. Components are reusable, self-contained building blocks for your UI. There are two types of components: functional and class components.

Functional Components (with Hooks):

import React, { useState } from 'react';

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

  return (
      <p>Count: {count}</p>
      <button onClick={() => setCount(count + 1)}>Increment</button>

export default MyComponent;

Class Components:

import React, { Component } from 'react';

class MyComponent extends Component {
  constructor(props) {
    this.state = {
      count: 0,

  render() {
    return (
        <p>Count: {this.state.count}</p>
        <button onClick={() => this.setState({ count: this.state.count + 1 })}>

export default MyComponent;

4. JSX and Rendering:

JSX is a syntax extension for JavaScript that looks similar to XML or HTML. It's used with React to describe what the UI should look like.

import React from 'react';

function App() {
  return (
      <h1>Hello, React!</h1>
      <MyComponent />

export default App;

5. Running Your App:

Back in your terminal, run:

npm start

This command starts the development server, and you can view your app at http://localhost:3000 in your browser.

Application structure

create-react-app gives us everything we need to develop a React application. Its initial file structure looks like this:

├── node_modules
├── package.json
├── package-lock.json
├── .gitignore
├── public
│   ├── favicon.ico
│   ├── index.html
│   ├── logo192.png
│   ├── logo512.png
│   ├── manifest.json
│   └── robots.txt
└── src
    ├── App.css
    ├── App.js
    ├── App.test.js
    ├── index.css
    ├── index.js
    ├── logo.svg
    ├── reportWebVitals.js
    └── setupTests.js

6. Learn and Experiment:

Explore the React documentation ( to deepen your understanding. Experiment with creating more components, using state and props, and incorporating other React concepts.

7. Tools and Extensions:

Consider using tools like React DevTools and VS Code extensions for React to enhance your development experience.

That's a quick start to React! As you become more comfortable, you can explore state management with Redux, routing with React Router, and integration with backend services. Happy coding!