React memo is a feature in React that enhances application performance by preventing unnecessary re-renders of components whose props remain unchanged. It employs memoization, a technique that caches function results to avoid repeated calculations, thereby optimizing the rendering process. When a parent component's state updates, React typically re-renders all child components, even if their data hasn't changed, which can degrade performance. By wrapping components in React.memo, a shallow comparison of props is conducted, ensuring only those with altered props are re-rendered, thus boosting efficiency. While effective for components with frequent prop changes or expensive rendering processes, React memo may not be beneficial for all scenarios and could introduce complexity if used unnecessarily. Developers are encouraged to use the React Profiler tool to identify when memoization would be advantageous. Additionally, other React performance optimization tools like useMemo and useCallback can be employed for more granular control over component updates. The article emphasizes the importance of performance optimization in maintaining responsive applications and suggests incorporating strategies like memoization, pagination, and lazy loading from the project's outset.