MSK Institute • Shikohabad
Loading Page Content...
Preparing courses, live labs, and learning resources.सामग्री लोड हो रही है, कृपया प्रतीक्षा करें...
Connecting serverPlease wait...
💻 Practical Labs🚀 Free Demo📜 Verified Certificates
Headings & Document Hierarchy (ATX vs Setext)0%
Headings & Document Hierarchy (ATX vs Setext)
Beginner12 min read•Updated: Jul 11, 2026
Headings establish the structural backbone of any document. They guide search engine crawlers (SEO), create clickable navigation outlines, and allow screen readers to parse the document hierarchy.
In Markdown, there are two distinct ways to create headings: ATX Style (using hash # symbols) and Setext Style (using underlines).
Click to Zoom1. ATX Headings (The Modern Standard)
ATX style headings are the most popular and versatile syntax in Markdown. You simply prefix the line with 1 to 6 hash symbols (#), followed by a space:
# Heading 1 (Page Title / <h1>)
## Heading 2 (Major Section / <h2>)
### Heading 3 (Sub-section / <h3>)
#### Heading 4 (Component / <h4>)
##### Heading 5 (Minor detail / <h5>)
###### Heading 6 (Deepest sub-item / <h6>)
Critical Rule: You MUST place a space between the last
# and the heading text!
- Correct: # Heading Title
- Incorrect: #HeadingTitle (Many modern CommonMark parsers will treat this as a hashtag or plain text rather than a heading!)Optional Closing Hashes (ATX Closed Style):
You can optionally close an ATX heading with matching hashes. The closing hashes are purely aesthetic and will not appear in the rendered output:
### Architecture Overview ###
2. Setext Headings (Underline Style)
Setext (Structure Enhanced Text) is an older style that mimics ASCII email conventions by underlining text with equal signs (=) or hyphens (-):
This is an H1 Heading
=====================
This is an H2 Heading
---------------------
- Equal signs (
=): Produce an<h1>tag. - Hyphens (
-): Produce an<h2>tag. - Any number of underlines (even 3 like
===or---) is sufficient. - Limitation: Setext only supports levels 1 and 2 (
<h1>and<h2>). It cannot create<h3>through<h6>.
3. Best Practices for Document Hierarchy
- 1Only One H1 per Document: Treat
# Heading 1as the title of your article or README. Use## Heading 2for main chapters, and### Heading 3for subtopics. - 2Never Skip Heading Levels: Do not jump directly from an
# H1to an### H3without an intermediate## H2. Skipping levels breaks accessibility for screen-reader users. - 3Keep Headings Concise: Headings are used by documentation generators (like VitePress and Docusaurus) to automatically generate page anchors (
#heading-slug) and sidebar Table of Contents.
Interactive Quiz
Multiple Choice Questions
Question 1
How many heading levels does ATX-style Markdown support?
Question 2
What character is used to create ATX style headings in Markdown?
Question 3
In Setext style headings, which heading levels can be created?
Question 4
Why must a space follow the hash symbol in '# Heading'?
Question 5
What HTML tag is generated by '### Database Configuration'?
Next Lesson
Paragraphs, Line Breaks & Horizontal Rules
Continue learning with hands-on practice, examples, and exercises in the upcoming topic.
Related Lessons
| Previous Lesson | Next Lesson |
|---|---|
| Environment & Editor Setup (VS Code, Obsidian, Typora) | Paragraphs, Line Breaks & Horizontal Rules |
Practice Quiz
Test your understanding of this lesson with 5 questions. Each question has one correct answer.