🔧 Next.js Caching Explained: Every Strategy You Need to Know (React cache, use cache, cacheTags & More)

Caching in Next.js has always been powerful. But since the App Router, it has also become deeply layered, sometimes confusing, and — if you get it wrong — quietly responsible for stale data, broken UIs, and slow apps.

This guide covers everything: React's cache() function, Next.js's new use cache directive, cacheTag, revalidateTag,...