useCallback is a Hook that returns a memoized version of a function, which only changes if one of its dependencies changes. It helps to prevent unnecessary re-creations of functions between renders, which is useful when passing functions to child components that rely on reference equality (like React.memo).

Syntax:

const memoizedCallback = useCallback(() => {
  doSomething(a, b);
}, [a, b]);

When to use useCallback:

• When passing functions as props to memoized components.
• When a function is used inside a useEffect dependency array.
• When you want to optimize performance by avoiding re-renders due to new function instances.

⚡ Quick Tip: Just like useMemo, don't use useCallback everywhere. It's mainly useful in performance-critical paths.

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