Yes, there are even documentations about documentation which is itself a bit of a paradox when you think about it. But there are many documentation sources out today for just that purpose. 

In fact Obsidian itself is a fantastic documentation source. It serves to explain and give tutorials for me. Just stick with one though. 

Documentation Sources: 
- Notion 
- Obsidian 
- Google Docs 
	- you can now publish anyth
- MkDocs