SWR is a React Hooks library for remote data fetching. It provides developers with a simple, yet powerful way to fetch, cache, and revalidate data in their components. Features include built-in caching, request deduplication, focus tracking, and revalidation on interval. SWR helps to improve performance and reduce unnecessary network requests, resulting in a better user experience by ensuring data is constantly fresh and available as needed. It's a great tool for managing server state.