React Tutorial

1. What is React & why should you use it?

React is a JavaScript library (not a full framework) created by Facebook (now Meta) in 2013. Its only job is to help you build beautiful, fast, and interactive user interfaces — especially for single-page applications (SPAs) like Instagram, Netflix, WhatsApp Web, Airbnb, etc.

Why do millions of developers (and companies) love React in 2026?

  • Component-based thinking → You build your UI like Lego blocks. Each piece (button, navbar, card, modal) is a reusable component. Change one → only that part updates. Super clean!
  • Declarative style → You just say what the UI should look like at any moment (based on data). React figures out how to make it happen efficiently.
  • Virtual DOM magic → React keeps a super-lightweight copy of the real webpage (virtual DOM). When something changes, it compares old vs new version and updates only the tiny parts that actually changed → insanely fast performance.
  • Huge ecosystem → React Router for navigation, Zustand/Redux for state, Tailwind for styling, Next.js for full-stack, shadcn/ui for beautiful components, React Query for data fetching… everything you need is already there.
  • React Native → Same code → mobile apps for iOS + Android.
  • Massive job market → Still the #1 most in-demand frontend skill in 2026 (way ahead of others).
  • React 19 (latest in 2026) → Even better forms, actions, server components, optimistic updates, new hooks like use, and improved performance.

Analogy: React is like a super-smart chef who only cares about cooking delicious food (UI). You tell him the ingredients (data/state), he prepares everything perfectly and serves it fast. Other tools might make you cook + wash dishes + clean the kitchen too.

2. React vs other popular frameworks/libraries (2026 comparison)

Framework/Library Type Learning Curve Speed (Dev + Build) Job Market (2026) Best For Community Love
React Library Medium Very Fast (with Vite) ★★★★★ (Biggest) Almost everything, especially SPAs & mobile (React Native) Very high
Vue 3/4 Framework Easy Fast ★★★★ Quick prototyping, progressive apps Very high
Angular Full Framework Steep Medium ★★★★ Enterprise, large teams, strict structure Medium
Svelte 5 Compiler Easy Blazing Fast ★★★ High-performance apps, small bundles Extremely high
Next.js (React) Meta-framework Medium Very Fast ★★★★★ Full-stack apps, SEO, server rendering Extremely high
Solid.js Library Medium Extremely Fast ★★ Performance freaks Growing

Quick verdict for 2026:

  • Want maximum jobs + huge community + works everywhere? → React (or Next.js built on React)
  • Want something super simple and beginner-friendly? → Vue
  • Want smallest bundle size + fastest runtime? → Svelte
  • Building big enterprise apps with lots of structure? → Angular

Most people (including me) recommend starting with React because:

  • You’ll learn concepts used everywhere
  • You can easily switch to Next.js, Remix, Vue, Svelte later
  • Biggest ecosystem & job opportunities

3. Setting up your development environment (2026 recommended way)

You need:

  1. Node.js → Latest LTS version (v20 or v22 in 2026) Download from: https://nodejs.org Check: Open terminal → node -v and npm -v
  2. Code EditorVS Code (free, best for React) Must-have extensions:
    • ESLint
    • Prettier
    • Tailwind CSS IntelliSense
    • React snippets (like “rafce” for component)
    • Auto Rename Tag
    • Bracket Pair Colorizer
  3. Best way to create a React app in 2026Vite + React (Create React App is officially deprecated — slow, old, not recommended anymore)
Bash

Boom! You now have a modern, blazing-fast React app with:

  • Instant Hot Module Replacement (changes appear in <1 second)
  • Super fast build times
  • Built-in TypeScript support (optional but amazing)

4. Your very first React app – let’s understand it!

Open the project in VS Code and look at src/App.tsx:

tsx

Super simple explanation:

  • function App() → This is your component (a function that returns UI)
  • useState(0) → Gives you a piece of state (like a memory box) + a function to change it
  • return (…) → This is JSX — looks like HTML but it’s JavaScript!
  • {count} → JavaScript expression inside curly braces
  • onClick={() => …} → When button is clicked, run this function

Your first exercise (do it now!):

  1. Change the <h1> to: <h1>Hello Webliance! Welcome to React 2026 🚀</h1>
  2. Add your name:
tsx
  1. Save → watch it update instantly! 🎉

Key Takeaways – Chapter 1

  • React = library for building fast, component-based UIs
  • Uses Virtual DOM → updates only what’s needed
  • Vite is the modern, fastest way to start React projects
  • JSX = HTML inside JavaScript
  • Components are just functions returning JSX
  • React 19 (2026) makes forms, data loading, and performance even better