React library VS framework
Why using framework
While React can be used without a framework, most applications and websites eventually require solutions for common challenges like bundling, compiling, code-splitting, routing, data fetching, and HTML generation. These issues aren’t unique to React but apply to all UI libraries. Using a framework from the start allows you to begin working with React more efficiently and avoids the need to create your own framework down the line.
Next.js
The Next.js team has been collaborating with React team in researching, developing, integrating, and testing framework-agnostic bleeding-edge React features like React Server Components.
Routing
A file-system based router built on top of Server Components that supports layouts, nested routing, loading states, error handling, and more.
Rendering
Client-side and Server-side Rendering with Client and Server Components. Further optimized with Static and Dynamic Rendering on the server with Next.js. Streaming on Edge and Node.js runtimes.
Data Fetching
Simplified data fetching with async/await in Server Components, and an extended fetch API for request memoization, data caching and revalidation.
Styling
Support for your preferred styling methods, including CSS Modules, Tailwind CSS, and CSS-in-JS
Optimizations
Image, Fonts, and Script Optimizations to improve your application's Core Web Vitals and User Experience.
TypeScript
Improved support for TypeScript, with better type checking and more efficient compilation, as well as custom TypeScript Plugin and type checker.