Understanding how websites render content is crucial for making informed architectural decisions. Let's demystify SSG, CSR, and SSR.
Client-Side Rendering (CSR)
Content is rendered in the browser using JavaScript.
How it works:
- Browser requests page
- Server sends minimal HTML + JS bundle
- JavaScript executes and renders content
- Data fetched via API calls
Pros:
- Rich interactivity
- Smooth page transitions
- Great for apps
Cons:
- Slower initial load
- SEO challenges
- Requires JavaScript
Frameworks: React, Vue, Angular (traditional SPAs)
Server-Side Rendering (SSR)
Content is rendered on the server for each request.
How it works:
- Browser requests page
- Server renders full HTML
- Browser displays content
- JavaScript hydrates for interactivity
Pros:
- Fast first contentful paint
- Great SEO
- Works without JS
Cons:
- Server load per request
- Slower time to interactive
- More complex caching
Frameworks: Next.js, Nuxt.js, Remix
Static Site Generation (SSG)
Pages are pre-rendered at build time.
How it works:
- Build process generates HTML files
- Files deployed to CDN
- Browser receives pre-built pages
- Optional hydration for interactivity
Pros:
- Fastest possible delivery
- Excellent SEO
- Low hosting costs
Cons:
- Build time for large sites
- Not suitable for dynamic content
- Requires rebuild for updates
Frameworks: Gatsby, Astro, Eleventy
Choosing the Right Approach
- CSR: Dashboards, apps with authentication
- SSR: E-commerce, social media, dynamic content
- SSG: Blogs, documentation, marketing sites