React

React is a UI library that lets you build interfaces from small, isolated pieces called components. Each component manages its own state and rendering logic, and you compose them together like building blocks to create complex applications.

React's component model is a perfect match for vibe coding. You can describe a component to the AI ("a card that shows a user's avatar, name, and join date with a hover effect") and get functional code because React components are self-contained and well-structured. The AI has extensive training data from millions of React projects.

Key concepts: JSX (HTML-like syntax in JavaScript), props (data passed to a component), state (data that changes over time), hooks (functions like useState and useEffect that add behaviour), and the virtual DOM (React's efficient rendering engine).