Static site generation
Also known as: SSG, Pre-rendering
Static site generation builds a website's pages into ready-made HTML files at build time rather than assembling them for each visitor.
In full
Static site generation compiles a website into finished HTML, CSS, and JavaScript files ahead of time, during a build step, rather than generating each page from a database when a visitor requests it. The resulting files can be served directly from a content delivery network with no server-side processing in the request path. This produces fast, cheap, and unusually secure sites: there is no database to inject, no admin panel exposed to the internet, and no plugin ecosystem to keep patched. Content is still editable, because a headless CMS can trigger a rebuild whenever something changes.
Why it matters
It removes the two most common sources of website trouble at once: slow, database-bound page loads and the security surface created by a live application handling every request.
A common misconception
That static means unchanging or unable to handle dynamic features. Forms, search, personalisation, and commerce all work; the dynamic parts run as isolated services rather than rendering the whole page.