Obsidian is a knowledge base that works on local Markdown files. Unlike Notion or Evernote, your data lives on your machine in plain text — you own it completely. Here’s how to start building your second brain.
Installation
brew install --cask obsidian
Or download from obsidian.md. Create a folder for your “vault” — this is where all your notes will live.
The Basics: Links and Backlinks
Obsidian’s superpower is linking. Type [[ and start typing a note name to create a link. Every linked note shows backlinks — a list of every other note that references it.
This creates a web of connected ideas that grows organically. You don’t need to organize files into folders; the links do the work.
Daily Notes
Enable the Daily Notes core plugin. Every day, Obsidian creates a new note (like 2026-07-13.md). Use it as a journal, task list, or catch-all for the day’s thoughts.
Set a template for daily notes in Settings → Daily Notes → Template file location.
Essential Plugins
Start with these built-in plugins:
- Templates — Create reusable note templates
- Graph View — Visualize the connections between your notes
- Canvas — A visual workspace for arranging notes, images, and cards
- Quick Switcher — Cmd+O to jump to any note instantly
Community Plugins Worth Installing
Once you’re comfortable, explore the community plugin store:
- Calendar — A visual calendar that shows which days have daily notes
- Dataview — Query your notes like a database
- Excalidraw — Draw diagrams directly in your notes
- Paste URL into selection — Paste a link as a formatted link with the selected text
Syncing Between Devices
Obsidian stores everything as plain Markdown files. Any file sync service works:
- iCloud Drive (free for Mac/iOS)
- Syncthing (free, self-hosted, peer-to-peer)
- Obsidian Sync (paid, official, end-to-end encrypted)
The mobile apps are full-featured and work offline. Your notes are just files in a folder — sync them however you want.