Day 4 — Markdown and Obsidian

Time: ~60 min · Date: Tue Apr 28

Why this matters

Your future notebook (Obsidian) uses markdown for formatting. Markdown is just text with simple rules. Once you've seen it, you'll see it everywhere — GitHub, Reddit, Discord, ChatGPT, this very file. It's worth 30 minutes of your life.

Markdown in 5 minutes

Markdown is text. You add a couple of special characters to format it. The plain text stays readable.

Headings

# This is a big heading
## Medium heading
### Smaller heading

Renders as:

This is a big heading

Medium heading

Smaller heading

Bold and italic

**bold text**
*italic text*
***bold and italic***

Lists

Bulleted:

- Apples
- Oranges
- Bananas

Numbered:

1. First
2. Second
3. Third

Checkboxes (super useful for to-dos):

- [ ] Unchecked task
- [x] Done task

Links

[Click me](https://example.com)

Renders as: Click me

Code (inline and block)

Inline: backticks around text → like this

Block: triple backticks above and below.

Tables

| Name | Phone |
|------|-------|
| Sarah | 555-1234 |
| Mark  | 555-5678 |

That's most of it

There's more (images, blockquotes, footnotes), but the above covers 95% of daily use.

Why markdown over Word

It's just text. Open it in any program, on any computer, in 30 years. No corrupted files.
It's fast. No mouse-trips to a toolbar. You just type.
Search is amazing. Plain text means every search tool can read it.
Plays nice with AI. Claude reads markdown natively. Your notes become things Claude can summarize, search, and build on.

What is Obsidian?

Obsidian is a folder of markdown files. That's it. The magic is the app on top:

A nice editor
Sidebar showing your folders
Backlinks (when one note references another, the other note knows)
Search across everything
Tags
A graph view that shows how your notes connect

But the files underneath are just text. You could delete Obsidian tomorrow and your notes would still open in any text editor. No vendor lock-in. That's the whole point.

How agents (could) use Obsidian

Some realistic patterns:

Daily notes — what's on your plate today, who you owe a call, what closed yesterday.
One folder per active client — first conversation notes, listings shown, contracts in flight.
One folder per active listing — seller details, marketing plan, showing log, offer history.
Reference folder — boilerplate emails, scripts, contract clauses you reuse, market data.
Templates folder — pre-made shells for common notes.

The win isn't "I have notes" — you already do that. The win is that everything is in one searchable place and Claude can read across all of it.

Exercise (~40 min)

You'll do this on your PC, then throw it away. The point is to feel the workflow.

Download Obsidian for Windows: obsidian.md. Free.
Install. When it opens, click Create new vault.
Name it practice. Pick any folder location.
Create these notes (use Ctrl+N for a new note):

Note: Listing - 123 Test St

# 123 Test St

**Client:** Sarah and Mark
**Listed:** April 26
**Asking:** $525,000

## Property notes

- 4 bed, 2.5 bath
- Renovated kitchen
- Mature landscaping
- Walking distance to a popular park

## Showings

- [ ] Saturday open house 11–1
- [ ] Tuesday private showing 6pm

Note: Daily - 2026-04-28

# 2026-04-28 Monday

## Schedule

- 10am call with [[Listing - 123 Test St]] sellers
- 2pm coffee with potential buyer

## Follow-ups

- [ ] Send disclosures to Maple Street buyer
- [ ] Confirm photographer for 123 Test

Notice that [[Listing - 123 Test St]] becomes a clickable link. That's a wikilink.
Click around. Try the search (top-left). Try the graph view (left sidebar, looks like dots).
When you're done, delete the practice vault folder. We'll set up the real one on the Mac.

Recap

You should now be able to:

Write a heading, a bulleted list, and a checkbox in markdown
Explain why markdown beats Word for daily notes
Describe what Obsidian is on top of
Create and link two notes in Obsidian

Going deeper (optional, ~50 min)

Watch (~25 min)

Search YouTube: "Obsidian for beginners 2024" — pick anything 15–25 min from a well-produced channel. Linking Your Thinking, Nicole van der Hoeven, and Bryan Jenks are reliable.
Search YouTube: "how I use Obsidian" — see how other people structure their vaults. Steal whatever looks useful.

Read (~25 min)

Markdown Guide — Cheat Sheet — single page reference, bookmark it.
Obsidian Help — official docs. The "Getting started" section is friendly.

Done?

Day 4 complete

Next: Day 5 — Terminal: not as scary as it looks

Lesson recap

Done with this lesson?

Mark it complete to track your progress.