What is the difference between Redux and React Context API?
Answer
Both Redux and React Context API share state across components, but they serve different purposes. React Context: built-in React mechanism for passing data deep into the component tree without prop drilling. Best for: relatively static data (theme, locale, current user) or data that changes infrequently. Context re-renders all consumers whenever the value changes — a performance concern for frequently-updated state. No built-in state management logic (no reducers, middleware, DevTools). Redux: dedicated state management library with predictable state transitions, middleware support, DevTools for time-travel debugging, and optimized subscriptions (only components that use a specific slice re-render). Best for: complex global state, frequent updates, state that multiple independent components need, or when you need middleware (logging, async operations). Modern advice: use Context for simple cases; use Redux Toolkit (or Zustand) for complex global state. React Query/TanStack Query handles server state better than both — many apps need minimal client state when server state is handled separately.