Obsidian Introduction
Obsidian is a bidirectional-link note-taking software based on local Markdown files. Officially positioned as your second brain (A second brain, for you, forever), it can help you weave scattered knowledge points into a growable knowledge network.
Obsidian is alocal-firstpersonal knowledge management tool.
Obsidian's core file format is plain-text Markdown. All notes are stored as.mdfiles in local folders on your computer.
Unlike online note tools such as Notion and Yuque, Obsidian does not require internet access; your data is completely in your own hands.
Compared with outliner-style note tools like Roam Research and Logseq, Obsidian is closer to the traditional document editing experience, allowing free writing while retaining powerful bidirectional linking capabilities.
Obsidian is to notes what VS Code is to code editing: not a closed platform, but an infinitely extensible tool. And because all your content is stored as plain-text files, you will always own them.
Why Choose Obsidian
| Feature | Obsidian | Notion | Roam Research |
|---|---|---|---|
| Storage Method | Local Markdown files | Cloud database | Cloud database |
| Offline availability | Fully offline | Requires preloading | Requires internet |
| Bidirectional linking capability | Native support | Limited support | Native support (outliner-style) |
| Extensibility | 1000+ community plugins | Few integrations | Fewer plugins |
| Price | Free for personal use | Freemium | Paid subscription |
| Data migration | Just copy the folder | Requires export | Requires export |
Obsidian's core essence can be summed up in three points:
- Plain-text storage: All notes are.mdMarkdown files in plain-text format, stored in a folder on your local computer. No proprietary format, no database; any text editor can open them.
- Bidirectional links: Notes can reference each other, forming a knowledge network rather than isolated files.
- Extensibility: With over 1,500 community plugins, you can turn Obsidian into whatever shape you need.
Why Obsidian Is Especially Suitable for Developers
Many tools can "take notes," but Obsidian has several unique appeals for developers.
Markdown Is Your Native Language
As a developer, you write READMEs, documentation, and comments every day.
Markdown is already part of your work. Obsidian treats Markdown as a first-class citizen, so there is no learning curve.
Local Files Mean Git-Friendly
All files are plain text, which means:
- You can usegit initfor version control of your entire vault.
- You can usegrep、sedand scripts to batch-process notes.
- Migration, backup, and export without any obstacles.
- Your data will never be taken away by the collapse of some company.
Programmer Mindset Aligns Perfectly with Obsidian
| Developer habit | Obsidian corresponding feature |
|---|---|
| Functions/modules referencing each other | Bidirectional links[[]] |
| Writing comments and documentation for code | Code blocks embedded in notes |
| Tracking changes with Git | Plain text + Git version management |
| Managing tasks with tags/branches | Tag system + folder structure |
| Consulting API documentation | Personal knowledge base + quick search |
| Project README | Project notes + Canvas whiteboard |
Core Differences from Mainstream Tools
Before choosing a tool, you need to understand each one's positioning to avoid redundant construction.
Obsidian vs Notion
| Comparison dimension | Obsidian | Notion |
|---|---|---|
| Data storage | Local plain-text files | Notion servers (cloud) |
| Offline availability | Fully offline | Requires network |
| Data ownership | You fully own it | Hosted by Notion company |
| Speed | Extremely fast, millisecond-level response | Depends on network speed, occasionally lags |
| Collaboration features | Weak (requires third-party tools) | Strong (naturally supports multi-user collaboration) |
| Degree of customization | Extremely high (rich plugin ecosystem) | Medium |
| Suitable scenarios | Personal knowledge management, deep thinking | Team collaboration, project management |
| Learning curve | Medium | Low |
Conclusion: If you need to collaborate with a team, Notion is more suitable. If you need to build a personal, long-term knowledge system, Obsidian is the better choice.
The two are not mutually exclusive; many people use both simultaneously.
Obsidian vs Roam Research
Roam Research is the pioneer of bidirectional-link note-taking, but Obsidian is the more practical choice:
- Roam is a SaaS subscription ($15/month), while Obsidian is completely free for personal use.
- Roam stores data in the cloud, Obsidian stores data locally.
- Roam's outliner-style structure is better for divergent thinking, while Obsidian's document-style structure is better for consolidation and organization.
Obsidian vs Typora / VS Code
These tools can also write Markdown, but they lack Obsidian's core capabilities:
- No bidirectional links: Files are isolated from each other and cannot form a knowledge network.
- No graph view: Cannot visually see the relationships between knowledge.
- No plugin ecosystem: Cannot extend functionality on demand.
Typora is an excellent Markdown editor, and VS Code is an excellent code editor, but neither is a knowledge management tool.
Obsidian's Core Philosophy
Before installing, establishing a few basic mental models will make subsequent learning twice as effective with half the effort.
Principle 1: Notes Are Files
Obsidian has no database or proprietary format of its own.
Every note is a.mdfile on your hard drive.
~/Documents/MyVault/
├── 日记/
│ ├── 2024-01-15.md
│ └── 2024-01-16.md
├── 技术笔记/
│ ├── Git 常用命令.md
│ └── Docker 入门.md
└── 读书笔记/
└── 深入理解计算机系统.md
When you create a note in Obsidian, you are actually creating a Markdown file in a folder.
You can see it directly in the file explorer, and usecatcommands to read it, and Git to track it.
Principle 2: Links Matter More Than Folders
Traditional note-taking software relies on folders to organize content, like putting books into different drawers.
This approach has a fatal flaw:A piece of knowledge can only belong to one drawer.。
Obsidian's core idea is: rather than putting notes into categories, connect them together.
# Docker 入门 Docker 是一种容器化技术，与 [[虚拟机]] 的关键区别在于... 在部署时，通常配合 [[Kubernetes]] 使用... 学习 Docker 之前建议先了解 [[Linux 基础]]...
When you open the note "Docker Getting Started", you will see it links to three notes: "Virtual Machine", "Kubernetes", and "Linux Basics".
At the same time, the note "Linux Basics" will also show that "a note called Docker Getting Started references me."
This isbidirectional linking, which simulates the way concepts are associated in the human brain.
Principle 3: The Knowledge Graph Is the Effect, Not the Cause
Many beginners see Obsidian's beautiful knowledge graph and mistakenly think that "building a knowledge graph" is the purpose of using Obsidian.
Then they spend a lot of time designing structures without actually taking notes.
The correct understanding is:The graph is a byproduct that naturally grows after you take notes and create links,not something you need to carefully design from the start.
Take notes first, create links first, and the graph will naturally become rich.
Principle 4: Never Chase a Perfect System
This is the trap beginners most easily fall into: spending too much time designing the "perfect" folder structure and tag system, rather than actually recording and thinking.
Other extensionsA "good enough" system that is consistently used is far better than a "perfect" system that has never truly been implemented.