React: What is Suspense?

What is React Suspense?

React Suspense is a feature introduced in React to help manage asynchronous operations more gracefully, improving your React applications' performance and user experience. It lets developers “suspend” the rendering of a component until some asynchronous resource is ready, such as data fetching or lazy-loaded components. In simpler terms, it allows you to pause the rendering process and show fallback content, like loading indicators, while the application is waiting for something, such as fetching data from an API or loading a component dynamically.

Suspense works seamlessly with other React features and is an integral part of the React ecosystem to optimize rendering and create a smoother experience for the user. To fully understand what Suspense is and how it works, we need to break it into smaller, digestible sections.

Why Suspense?

Before React Suspense, developers had to manually handle the complexity of loading states in their components. For example, in data fetching scenarios, developers had to set up useEffect, manage loading states (isLoading, hasError, etc.), and conditionally render loading spinners or error messages. Suspense simplifies and abstracts this boilerplate code, allowing developers to declaratively specify loading states.