Client-side rendering (CSR) generates page content in the user’s browser using JavaScript after the initial page load. Server-side rendering (SSR) generates the full page HTML on the server before delivery, so the complete content is present in the initial response. Static site generation (SSG) pre-renders pages at build time.
AI crawlers generally cannot execute JavaScript, which means CSR pages may be indexed as empty or near-empty. SSR and SSG ensure that content is present in the HTML that crawlers receive. For Next.js sites specifically — a very common modern React framework — SSR and SSG are built-in options that make AI discoverability straightforward to achieve without sacrificing the benefits of a JavaScript frontend.