Static site generators (SSGs) like Next.js, Gatsby, and Hugo compile a website into plain HTML, CSS, and JavaScript files before deployment. Because pages are pre-rendered, they load extremely fast and require no server-side processing per request, resulting in excellent performance and security. SSGs are often paired with a headless CMS in a JAMstack architecture. They are well-suited for marketing sites, blogs, and documentation where content changes are managed through a build pipeline.