I recently came across this information when reading who can view material in Knowledge Base (of Jira Service Management):
All logged-in users: Choose this option if you want to make articles in this space visible only to users who are logged in to your service project or help center. Your team will be able to view these articles in your service project and in the help center. And your logged-in customers will be able to view them in the help center. These articles are also visible to all active Atlassian account users. However, they can only view these articles in Confluence.
Only Confluence users: Choose this option if you want to restrict access to articles in this space to licensed Confluence users who have access to this space.
What is the difference between these logged-in users and Confluence users? We currently provide our company access to our Confluence spaces but not our customers. We are considering using Jira Service Management Knowledge Base to link a Confluence space that houses our software manual so that our users (customers of our software) have access to the content from within our software. I'm trying to decipher who logged-in users would be if I don't want anyone, including search engines, to find the content.