Introduction to React
Harry
· 28 Sep 2026
· 3 views
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What is React?
React is a JavaScript library by Meta for building user interfaces from small reusable pieces called components. Instead of manipulating the DOM by hand, you describe what the UI should look like and React updates it efficiently.
Why React Dominates Frontend Jobs
- Component model - build once, reuse everywhere.
- Huge ecosystem - Router, Next.js, React Native, testing tools.
- Virtual DOM - minimal real DOM updates, fast apps.
- Jobs - the most demanded frontend skill worldwide.
React vs Angular vs Vue in One Minute
- React is a library (UI only) - you pick router, state, backend.
- Angular is a full framework - batteries included, steeper curve.
- Vue sits in the middle - gentle but smaller job market.
What You Will Build Here
Book catalog app, quiz app, blog with Next.js, auth-protected dashboard - every lesson ships runnable code in the companion repo.
- React describes UI; it handles DOM updates for you.
- Components are functions returning UI.
- This track ends with deployed Next.js projects.