Server-Side Rendering (SSR)
A rendering approach in which the server generates the full HTML for a page on each request before sending it to the browser.
Sites built on JavaScript frameworks risk slow first loads and incomplete indexing if content appears only after client rendering; SSR puts key content and links in the first response, supporting search visibility and conversion.
An ecommerce catalog built with React moves product pages to SSR in Next.js, caches rendered HTML at the CDN for 60 seconds, and uses URL Inspection in Search Console to confirm product names and prices appear in the HTML.
Rendering on every request adds server cost and can raise Time to First Byte without caching. Hydration can still delay interactivity, and SSR does not help content blocked by robots.txt or pages slowed by heavy client scripts.
On each request the server runs the application code, fetches data and returns complete HTML, which generally gives a fast First Contentful Paint. The browser then hydrates the page by attaching JavaScript event handlers. Alternatives include static rendering at build time and client-side rendering. Google renders JavaScript in a deferred queue, and its JavaScript SEO guidance still recommends server-side or pre-rendering, which supports Indexability and Core Web Vitals.
Experience Design, Search Optimization
web.dev — Rendering on the Web — https://web.dev/articles/rendering-on-the-web; Google Search Central — Understand JavaScript SEO basics — https://developers.google.com/search/docs/crawling-indexing/javascript/javascript-seo-basics
