Markdown is everywhere developers write: README files, issue trackers, documentation, chat apps and note tools. Its genius is letting you format text using punctuation you would type anyway, so the source stays readable even before it is rendered. This guide covers the syntax and why it became a standard.
The core syntax
- Headings — one to six # characters before the text.
- Emphasis — *italic* with single asterisks, **bold** with double.
- Lists — a dash or asterisk for bullets, numbers for ordered lists.
- Links — [text](url); images add a leading exclamation mark.
- Code — backticks for inline code, triple backticks for blocks.
- Quotes — a leading > for blockquotes.
Why plain text won
Markdown’s key insight is that the source should be readable as-is. A Markdown document looks sensible in a plain editor, unlike HTML or word-processor formats full of tags or hidden state. That readability makes it perfect for version control, where you want to see exactly what changed, and for writing quickly without lifting your hands from the keyboard.
Flavours and extensions
There is a core Markdown everyone shares, plus extensions that vary by platform. GitHub Flavored Markdown adds tables, task lists, strikethrough and automatic links, and is the de facto standard in developer tools. When something renders differently than expected, a flavour difference is often why.
Tips for clean Markdown
Keep a blank line between block elements so they render reliably. Use reference-style links to keep long paragraphs readable. And preview your Markdown before publishing — small mistakes like a missing blank line before a list are the usual cause of formatting that looks wrong.
The takeaway
Markdown gives you formatted output from text that stays human-readable at the source. Learn the handful of core symbols and you can write clean docs, READMEs and notes anywhere, with formatting that travels across tools.