What is Obsidian?
Obsidian is a knowledge-management app for writing notes in Markdown. It works as a straightforward note-taking tool, but its defining feature is the ability to link notes together and grow them into a personal knowledge base. It is often used as a tool for building a “second brain.”
How is it different from a typical notes app?
Obsidian normally stores each note as a plain-text file on your own computer. The files are not locked into a format that only one company’s service can open, which makes it easier to choose your own editor, backup method, and long-term storage.
Links between notes are the other major difference. You can keep separate notes for people, projects, books, and meetings, then connect them so related information is easy to revisit. This preserves relationships that a folder hierarchy alone cannot express.
What can you use it for?
- Collect material for work and personal projects
- Keep reading notes or a long-term journal
- Connect article outlines, drafts, and references
- Build a personal knowledge base that an AI can read
Plugins can add task management, database-like views, and many other features. It is still best to begin simply: write useful notes and link only what needs to be connected. A complex setup can easily turn organizing into the project itself.
Why does it matter in the AI era?
An AI can give more relevant answers when it has concrete source material and context. Notes about past work, decisions, failures, and successes can become a durable body of context that you selectively share with an AI.
Owning the files does not mean every note should be sent to an external AI service. Check the scope before sharing personal or confidential information, and provide only the material needed for the task.