Managing server state in React applications often brings unique challenges that go beyond handling local component state. While local state is concerned with UI interactions and temporary data, server state involves data fetched from remote sources, such as APIs or databases. This data can change outside the application's control, making it difficult to keep the UI in sync with the latest server data. Some common challenges include:

• Keeping data fresh when it might change on the server;
• Handling loading and error states consistently;
• Avoiding unnecessary network requests and redundant data fetching;
• Synchronizing shared data across multiple components;
• Managing caching, background updates, and refetching logic manually.

React Query was created to simplify these complexities. It provides a set of tools that make fetching, caching, synchronizing, and updating server state in React applications much more manageable and reliable.

React Query offers several core features that address the pain points of server state management:

• Data fetching: simplifies requesting data from APIs and tracking the request status;
• Caching: automatically stores fetched data, reducing redundant requests and improving performance;
• Background updates: keeps data up to date by refetching in the background when needed;
• Synchronization: ensures multiple components using the same data stay in sync, even if the data changes elsewhere.

By handling these concerns for you, React Query lets you focus on building features instead of writing boilerplate code for data management.