Server-Side vs. Client-Side Rendering

Server-side rendering (SSR) generates a page's full HTML on the server before sending it to the browser; client-side rendering (CSR) sends minimal HTML and builds the page in the browser using JavaScript.

SSR content is present in the initial HTML response, which is the safest, most reliable path for search engine visibility. Pure CSR requires the crawler to execute JavaScript before the real content exists — see rendering for why that's slower and less reliable than it sounds. Dynamic rendering (serving a pre-rendered, crawler-specific version to bots while serving the normal CSR app to real users) is a workaround some sites use, though modern frameworks increasingly make full CSR-only architectures for SEO-critical pages unnecessary.