GLOSSARY
Headless CMS
A headless CMS is a content management system that stores and manages content but has no built-in front end to display it, instead exposing content through an API that a separately built site, static or otherwise, pulls from and renders however it chooses.
Why it matters
It lets a team keep a familiar, non-technical content editing interface while the actual site stays fast and static, decoupling how content is written from how it is displayed. This is the practical way to combine static site generation's speed with a CMS's easy editing workflow. It also future-proofs the content itself: because content lives in the CMS independent of any one front end, it can be reused across a website, a mobile app and other channels without being re-entered or restructured for each one. It also decouples release schedules: content changes can go live independently of code deployments, and code changes do not require a content team to be involved at all.
What goes wrong when it's handled badly
Treating a headless CMS as a drop-in replacement for a traditional one without planning the build step and content-refresh workflow leads to a site where editors publish a change and are confused it does not appear instantly, since a static build genuinely has to rebuild and redeploy to reflect it. That trade-off is manageable when it is planned for, and a source of real confusion when it is not explained upfront. A concrete example is an editor adding a new content field in the CMS that the front-end code was never updated to display, so the change appears saved and successful on the editing side while having no visible effect on the live site at all. Keeping the CMS's content model and the front end's rendering logic in sync deliberately, through a documented process rather than informal coordination, is what prevents this class of silent mismatch.