What are useMemo and useCallback hooks in React and when should we ideally use them.

Question

Accepted Answer

useMemo and useCallback are React hooks used for performance optimization by memoizing values and functions respectively.

useMemo is used to memoize the result of a function so that it is only recomputed when its dependencies change.
useCallback is used to memoize a function instance so that it is not recreated on every render.
useMemo is ideal for optimizing expensive calculations or complex operations that do not depend on props or state changes.
useCallback is ideal for optimizing functions that are passed down to child components and have dependencies.
Both hooks help in preventing unnecessary re-renders and improving the performance of React components.

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