React is the most-installed JavaScript view library on the web. Facebook open-sourced it in 2013 to solve one specific problem: keeping the UI in sync with rapidly-changing application state without reaching for two-way data binding.
React isn't a full framework. It gives you a way to describe UI as functions of props and state, then leaves routing, data fetching, forms, and styling to libraries you pick yourself. A real-world React project almost always means React plus Next.js (or Remix), TanStack Query (or SWR), and a state library like Zustand or Redux Toolkit.
What you'll work with in these 190+ courses
- Hooks-first patterns:
useState,useEffect,useReducer, custom hooks - Server Components and the App Router introduced in React 19 / Next.js 14+
- State management: Context, Zustand, Redux Toolkit, Jotai, Recoil
- Data fetching: TanStack Query, SWR, Server Actions, RTK Query
- Testing: React Testing Library with Vitest or Jest, Playwright for end-to-end
- Performance work:
memo,useMemo,useCallback, code-splitting, Suspense boundaries
Facebook, Instagram, WhatsApp Web, Netflix, Airbnb, Shopify, and the AWS console all run on React. The library handles UI for dashboards, social feeds, e-commerce frontends, internal admin tools, and React Native apps that share business logic between web and mobile.
