When working with your content — authoring, editing, reviewing, etc. — you work with a project that is unavailable to your readers. Only logged-in Contributors have access to it.
For the content to become available to the readers, you need to publish your project — i.e., create an online publication or create an output in one of the formats supported by ClickHelp. The publishing process creates an online or downloadable version of your project, taking a snapshot of the project at the moment of publishing.