React Tutorial for Beginners

React is one of the most popular JavaScript libraries for building user interfaces. It was created by Meta (Facebook) and is used by companies worldwide to build modern web applications.

Why Learn React?

Huge industry demand
Component-based architecture
Fast and efficient UI updates
Large ecosystem
Works perfectly with Next.js

What Can You Build With React?

Web Applications
Dashboards
Admin Panels
E-commerce Websites
Social Platforms

What is a Component?

Components are reusable building blocks of React applications.

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

JSX

JSX allows HTML-like syntax inside JavaScript.

const element = (
  <h1>StudyForge</h1>
);

Props

Props allow data to be passed between components.

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

State

State allows components to store changing data.

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

useState Hook

import { useState } from "react";

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

  return (
    <button onClick={() => setCount(count + 1)}>
      {count}
    </button>
  );
}

useEffect Hook

import { useEffect } from "react";

useEffect(() => {
  console.log("Component mounted");
}, []);

Event Handling

function Button() {
  return (
    <button onClick={() => alert("Clicked")}>
      Click Me
    </button>
  );
}

Forms in React

const [name, setName] = useState("");

<input
  value={name}
  onChange={(e) => setName(e.target.value)}
/>

React Learning Roadmap

JavaScript Fundamentals
Components
Props
State
Hooks
Forms
Routing
API Integration
Next.js

React Interview Questions

What is React?

React is a JavaScript library used to build user interfaces.

What is JSX?

JSX is a syntax extension that allows HTML-like code inside JavaScript.

What are Props?

Props are used to pass data between components.

What is State?

State stores data that changes during a component's lifecycle.

What is useEffect?

useEffect handles side effects such as API calls and subscriptions.

Frequently Asked Questions

Should I learn JavaScript before React?

Yes. Strong JavaScript fundamentals are essential for React.

Is React still worth learning?

Yes. React remains one of the most popular frontend technologies.

Is React a framework?

React is technically a JavaScript library.