Recommended and mentioned products
Manage your Notes from any Git Repo.
a non-linear personal web notebook
Seems like a simpler version of TiddlyWiki¹, which is free. It might worth a try for those who prefer less features : https://tiddlywiki.com/.
Zim is a graphical text editor used to maintain a collection of wiki pages. Each page can contain links to other pages, simple formatting and images.
Related software and previously discussed on HN - ZimWiki https://zim-wiki.org/ It lets you run a Wiki out of a vault in your drive, which can be moved to a new machine or exported as PDF/HTML.
Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, tagged and modified either from the applications directly or from your own text editor.
I have been using Joplin (https://joplinapp.org/) for a while now. I like it so far.