From what I can tell I can create a 'Space' in Confluence where I can store user guides etc that have been created for various bits of hardware or software that we've built. Version control is built into the system. Some of these user guides would need to be accessed by users external to my company, i.e. customers that have purchased a software licence requiring a user guide to navigate (not all our products have proper 'help'). There would also be other company staff requiring this access that are not a part of the team or currently use Atlassian.