What is Next.js?
Why Interviewers Ask This
Interviewers use this question to quickly assess whether a candidate has the foundational knowledge required for Next.js development. It reveals whether you understand the building blocks that more complex concepts rely on.
Answer
Next.js is an open-source React meta-framework created by Vercel (formerly Zeit) that adds server-side capabilities, file-based routing, and powerful build optimizations on top of React. It enables building full-stack web applications with React. Key features: (1) Multiple rendering strategies: Server-Side Rendering (SSR), Static Site Generation (SSG), Incremental Static Regeneration (ISR), and Client-Side Rendering (CSR) — per page or even per component; (2) File-based routing: the directory structure automatically defines routes — no manual router configuration; (3) Server Components: React Server Components allow rendering on the server with zero JavaScript sent to the client; (4) API Routes: create backend API endpoints within the Next.js project; (5) Automatic code splitting: each page loads only the JavaScript it needs; (6) Image, Font, and Script optimization; (7) TypeScript and Tailwind CSS: built-in support out of the box. Next.js is the most popular React framework, used by Vercel, TikTok, Hulu, Twitch, Nike, and thousands of other companies. Latest major version: Next.js 14/15 with the App Router as the stable primary routing approach.
Common Mistake
Rushing to answer is a common mistake. Take two seconds to structure your response: definition → example → trade-off. This structure makes complex Next.js answers easy to follow.