What Markdown Is
Markdown is a way to format text using simple symbols instead of buttons and menus. Instead of clicking a "Bold" button like in Word, you wrap text in asterisks. Instead of selecting "Heading 1" from a dropdown, you put a hashtag before the line.
The file extension is .md. A markdown file is just a text file with formatting symbols. It is lightweight, portable, and readable by every AI tool, code editor, and development platform. There is no special software required to create or read it.
The Five Symbols You Need
| Symbol | What It Does | Example |
|---|---|---|
| # (one hashtag) | Main heading | # Business Context |
| ## (two hashtags) | Section heading | ## My Audience |
| - (dash) | Bullet point | - Non-technical founders |
| **text** (double asterisks) | Bold text | **important note** |
| > (angle bracket) | Quote or callout | > Key insight here |
That is it. Five symbols. You can learn them in ten minutes and use them forever. Everything else in markdown is optional and useful but not required for AI work.
Why AI Reads Markdown Best
When you paste a Word document into Claude, Claude receives flat text with no visible structure. The formatting -- headings, bold, sections -- is stripped away. Claude has to guess where sections begin and end.
When you give Claude markdown, the structure is explicit. Claude sees the hashtags and knows exactly where each section starts. It sees the dashes and knows what the bullet points are. It sees the bold markers and knows what you emphasized. This clear structure helps Claude understand the hierarchy and relationships in your content.
Markdown is how you give AI structured information without any ambiguity. The symbols are simple for you to write and clear for AI to read. That combination is why markdown became the standard format for AI context files.
Where to Use Markdown
Business Context Document. Write your BCD in markdown with clear headings for each section. Upload it to a Claude Project. Claude reads the structure perfectly.
Prompts. Structure your prompts with markdown headings and bullet points. Claude follows structured prompts more precisely than wall-of-text prompts.
Documentation. README files, project descriptions, and internal documentation are all typically written in markdown. Every platform from GitHub to Notion renders markdown automatically.
Replit files. When you build with Replit, project documentation and configuration notes use markdown. Understanding the format means you can read and edit these files confidently.
How to Start Using Markdown
Open any text editor. Start typing with the five symbols above. Save the file with a .md extension. That is a markdown file. Upload it to a Claude Project and test the results.
The fastest way to practice is to rewrite your Business Context Document in markdown. Add hashtag headings for each section. Use dashes for key details. Bold the most important terms. Upload it to Claude and compare the output quality to your previous version.