Next.js is a React framework for building websites and web applications. It extends React with features such as routing, server rendering, and backend functionality. These capabilities help developers create complete applications while keeping their code organized around pages, layouts, and reusable components.

One of Next.js’s main strengths is its support for different rendering approaches. Developers can generate pages ahead of time, render content on the server when requested, and add interactive features through client components. This flexibility helps applications balance loading performance, content freshness, and user interaction.

Next.js uses file-based routing, where folders and files define application routes. Shared layouts allow pages to reuse interface elements such as navigation bars and footers. It also provides tools for optimizing images, loading fonts, and managing page metadata, supporting efficient delivery and search engine visibility.

Developers can connect Next.js applications to databases, authentication services, and external APIs. Server-side functionality supports tasks such as processing forms and retrieving protected data. From blogs and portfolios to online stores and SaaS platforms, Next.js provides a structured foundation for building applications with React.