Introduction to React

React is a JavaScript library for building user interfaces, particularly web applications. It was created by Facebook and is now maintained by Facebook and the community.

What is React?

React is a declarative, efficient, and flexible JavaScript library for building user interfaces. It lets you compose complex UIs from small and isolated pieces of code called "components."

Why React?

• • Component-Based: Build encapsulated components that manage their own state


• • Declarative: Describe what the UI should look like for any given state


• • Learn Once, Write Anywhere: Use React for web, mobile, and desktop apps


• • Virtual DOM: Efficient updates and rendering


• • Rich Ecosystem: Large community and extensive tooling

Key Concepts

• • Components: Reusable pieces of UI


• • JSX: JavaScript syntax extension for writing HTML-like code


• • Props: Data passed down from parent to child components


• • State: Data that belongs to a component and can change over time


• • Virtual DOM: JavaScript representation of the real DOM

Getting Started

To start with React, you need:

• 1. Node.js installed on your computer


• 2. A code editor (VS Code recommended)


• 3. Basic knowledge of HTML, CSS, and JavaScript

React vs Other Frameworks

React focuses on the view layer and works well with other libraries and frameworks. It's often compared to Angular and Vue.js, but each has its strengths.