At work we are using Confluence and GitHub.
What to put in Confluence and what to put in GitHub?
When to use GitHub wiki vs checked-in documentation?
How to deal with information vs knowledge?
How to avoid outdated documentation?
Put business details in confluence and the technical in Github.<p>Business details:<p>* Product purpose - What it does.<p>* Business justification - Much money it generates or saves the company.<p>* Product Owner<p>* Business alignments/dependencies<p>Technical stuff:<p>* Describe what the product actually does, as opposed to what it claims to do.<p>* List all build and installation steps.<p>* Document how to run tests.<p>* Document technical requirements and business flow through the application.<p>* Try to autogenerate the areas of documentation that are most likely to go out of date. I wrote a build step in my Node.js app that does this so I don't have to manually maintain a good portion of the documentation.