React Basics – Easy Study Notes for Beginners

📘 What is React?

React is a JavaScript library used to build user interfaces, especially for websites and web apps.

📘 Why use React?

• Fast performance

• Reusable components

• Easy to manage UI

• Strong community support

📘 What is a Component?

A component is a small part of the UI.
It can be reused again and again.

👉 Example: Navbar, Button, Card

📘 Types of Components

1. Functional Component

• Simple function

• Most commonly used

2. Class Component

• Older method

• Uses classes

📘 What is JSX?

JSX is a syntax that looks like HTML but works inside JavaScript.

👉 Example:
<h1>Hello World</h1>

📘 What is State?

State is used to store data inside a component.
It can change over time.

📘 What are Props?

Props are used to pass data from one component to another.

📘 React Hooks

useState

• Used to manage state

useEffect

• Used for side effects like API calls

📘 Advantages of React

• Fast rendering

• Easy to scale

• Code reuse

• Large ecosystem

📘 Disadvantages

• Learning curve for beginners

• Needs extra tools

🔁 Flashcards (Study Mode)

Q: What is React?
A: A JavaScript library for building UI

Q: What is a component?
A: A reusable part of UI

Q: What is JSX?
A: HTML-like syntax in JavaScript

Q: What is state?
A: Data stored inside a component

Q: What are props?
A: Data passed between components

Q: Name two React hooks
A: useState, useEffect