Modern Next.js

To use Server and Client Components in the Next.js App Router, apply the 'use client' directive only when client-side interactivity is needed, keeping the rest as Server Components to optimize performance and maintainability.

The best way to fetch data in Next.js Server Components is to fetch directly inside the component, leveraging the App Router's built-in caching mechanisms to ensure efficient data retrieval and performance.

Handle data mutations with Server Actions in Next.js by defining async functions that securely process form submissions, including built-in validation and automatic cache revalidation to update data.

Caching in the Next.js App Router works by automatically storing fetched data and rendered routes, which you can manually revalidate using Server Actions to ensure optimal performance and fresh content.

Generate dynamic metadata in a Next.js application by exporting a dynamic `generateMetadata` function from your `page.tsx` or `layout.tsx` files, allowing you to define SEO tags based on route parameters.