Mastering Next.js Rendering

Next.js is the industry standard for React applications. It provides multiple ways to render your app. The "Best" way depends on one question: When do you have the data?

1. Static Site Generation (SSG)

Render the page at Build Time. The HTML is static and served via a CDN. Pros: Fastest possible speed. Cons: Data can get stale if not rebuilt.

2. Server-Side Rendering (SSR)

Render the page on Each Request. The server fetches fresh data and sends a fully-formed HTML page to the browser. Pros: Always fresh data. Cons: Slower because the user has to wait for the server and API calls.

3. Incremental Static Regeneration (ISR)

The "Silver Bullet." Next.js serves the stagnant page immediately (fast) but re-generates it in the background every X seconds. This gives you the speed of SSG with the freshness of SSR.

4. Interview Mastery

Q: "When would I choose Next.js over a standard Vite (SPA) app?"

Architect Answer: "I choose Next.js when **SEO** and **First Contentful Paint** are critical. A standard Vite app is a 'Client Side App'—the browser gets an empty div and then JS has to download and run before the user sees anything. Next.js sends the content *immediately* as HTML. This leads to better search ranking and higher conversion rates."