I'm looking for a personal knowledge manager, that can be used by multiple people with different accounts.
It should be web-based and free and preferably open-source. Situation is as follows, I do something, it might be hard it might be easy, I want to write it down. Normally, I'd use plain paper, but it's really easy to lose track of everything I write down, so I prefer a digital solution.
I've looked at wikis, but I'm not a great fan of them, in the way that they are structured. They are structured as linked bits of information, instead, when I'm working on a project, the information has a very clear relation, day one, I do this, day two, I do that, while a wiki is great at sharing information, it's not good at sharing a roadmap of where you started, and where you ended up.
The advantage of such a system is that you can easily share it with someone, and without an explanation, they can end up where I ended up.
Preferably, such software should be free, open-source and self hostable, we don't live in a perfect world though, so I'm not sure if there is such a thing. As for technical requirements, I should be able to write text, use a markup language (Markdown, BBCode, HTML, anything) or a WYSIWYG editor, I prefer the luxury of both.