NextJS

React Server Components (RSC): Reduces the client-side bundle size by rendering components server-side, directly accessing the backend. It’s great for performance optimization, reducing initial load times and strengthening SEO capabilities.

Middleware provides granular control over the request-response lifecycle, enabling refined server-side logic like A/B testing and request manipulation. It’s admired for customizing user experience and implementing complex server-side logic efficiently.

Edge Functions: By running server-side code at the network’s edge, Edge Functions minimize latency, offering a serverless experience. It’s needed in applications requiring high performance and low response times, particularly for global user bases.

App Router: A real star among these improvements! It changes the routing system in Next.js framework, and supports advanced features like nested routes and layouts. It’s a more flexible and powerful way to structure applications, crucial for large-scale and complex web projects.