Next.js adds server rendering, a built-in router and backend code in the same project, which Create React App leaves to you. The React team has also deprecated Create React App for new apps. The main benefits are:
Server-side rendering and static generation send finished HTML, which helps SEO.
Routing is file-based, so a file or folder becomes a URL.
API routes let you build backend endpoints in the same project.
Next.js splits code automatically and produces optimized production builds with minimal configuration.
The Image component resizes, compresses and lazy-loads images.
Development includes hot reloading, TypeScript support and better error messages.
Create React App renders everything in the browser and has no built-in routing or data fetching.
Rewriting in plainer words…
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