useEffect in React

React provides powerful hooks like useEffect and useContext for managing component behavior. useEffect handles side effects such as API calls and timers, with its execution controlled by a dependency array to run once, on every render, or upon specific state changes. Meanwhile, useContext enables components to access shared data from a Context Provider, effectively eliminating prop drilling. Common use cases for Context include managing themes, user authentication, language settings, and shopping cart data across the component tree.