Obsidian is a world-class note-taking and personal knowledge management application. You can install and run a full-featured version, without charge, across multiple platforms (Mac, Windows, Linux, IOS/Android), and devices (phones, tablets, laptops, desktops).

I have written the second version of a beginner's tutorial to Obsidian. You can purchase it on Kindle, or access it through Kindle Unlimited. From there, you can also request a copy of the Obsidian vault from which the ebook was published. I am planning to publish an expanded, and extended, version of the tutorial in late spring, 2023.

My personal history goes back to the early days of the web, including a consulting gig to a then-leading hypertext tool, and a Random House tome on multimedia content creation. I make use of Obsidian for personal research of various kinds, including genealogical, but it is superbly suited for note-taking by students, teachers and researchers across many fields. Check out the Obsidian forum to get a sense for the user community and its applicability across many domains.