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•Question 5 of 48mediumuseEffect Hook
Handling side effects in React.
What is useEffect?
useEffect lets you perform side effects in functional components. Side effects include data fetching, subscriptions, DOM manipulation, etc.
When Does useEffect Run?
- No dependency array: Runs after every render
- Empty array []: Runs only on mount
- With dependencies [a, b]: Runs when a or b changes
Cleanup Function
Return a function from useEffect for cleanup (unsubscribe, clear timers, etc.)