Next.js 14 App Router: Best practices

Next.js 14 and the App Router represent a paradigm shift in how we build React applications. Moving from the Pages router requires unlearning some old habits.

Key Concepts - **Server Components by Default:** Fetch data directly in your components without `useEffect`. This reduces bundle size and improves SEO. - **Client Boundaries:** Only use `"use client"` when you need interactivity (e.g., `useState`, `onClick`). Push client components down the tree as far as possible. - **Data Caching:** Understand how `fetch` is cached in Next.js. Use `revalidate` tags to trigger targeted cache invalidations when data changes.

The App Router is complex, but mastering it allows you to build incredibly fast, dynamic web applications with excellent developer experience.