Oddbean new post about login | logout You can basically make your own wiki with it, and write everything in markdown. It's nifty. It also has a canvas flowchart mindmap function
It looks easy too much for my meager mental capacity to handle.
It's super simple interface. I use it for work, and also my public domain books collection from Internet archive and project Gutenberg. I download the .txt version, import it, and can tag, hyperlink, drop images, etc.