React Fundamentals Refresher

Explain how functional components mount, update, and unmount in the context of React's hooks lifecycle.

Use `useState` and `useReducer` to manage local component state for different complexity levels.

Implement `useEffect` with correct dependency arrays to handle side effects.

Implement cleanup logic within `useEffect` to prevent memory leaks from subscriptions, timers, or event listeners.

Apply `useMemo` and `useCallback` to prevent unnecessary re-computations and re-renders.

Create custom hooks to extract and reuse stateful logic across components.