Suspense
Suspense is a React feature that allows components to 'wait' for something before rendering, such as data fetching, code splitting, or other asynchronous operations. It provides a declarative way to handle loading states and fallback UIs, improving user experience by managing pending states gracefully. Suspense works by suspending rendering until the awaited data or code is ready, then resuming with the resolved content.
Developers should use Suspense when building React applications that involve asynchronous data fetching, lazy-loaded components, or any operation where content might not be immediately available. It's particularly useful for creating smoother loading experiences, reducing boilerplate code for loading states, and enabling concurrent features in React 18+. For example, it can be used with React.lazy for code splitting or with libraries like Relay or SWR for data fetching.