Next.js Router Cache: Unlocking Instant Navigation Performance

Router cache is a critical client-side mechanism in Next.js that caches visited pages and prefetched resources in browser memory to enable instant navigation between pages. Understanding cache duration, automatic invalidation periods, and explicit revalidation strategies through Server Actions is essential for optimizing performance and preventing stale data. The distinction between static and dynamic page caching, along with cache invalidation for authentication changes, represents key considerations for developers building performant Next.js applications.