Hugo is a static templating system. It is (mainly) used to deploy websites/blogs which don’t have and need dynamic content. The content of all pages is pre-generated, and the webserver delivers files from disk (or rather from cache, once files are loaded into memory). This approach allows for extremely fast websites, as no dynamic content is generated on every request.
While I know Hugo from work, I haven’t really used it for private projects - until recently. I have started a new project where I present interviews with people behind the PostgreSQL Project - and this is perfect for a static website. Interviews don’t change, once published.