Markdown Cheat Sheet
Markdown has a small syntax, yet a few details always slip: how table alignment works, how to get a code block highlighted, what goes inside a task-list bracket. This page tabulates the core syntax and the GitHub extensions separately for quick lookup.
Core Syntax
| Element | Syntax | Note |
|---|---|---|
| Heading | # H1 … ###### H6 | Six levels; a space follows the hashes |
| Bold | **粗体** | Bold text |
| Italic | *斜体* | Italic text |
| Bold italic | ***两者*** | Both bold and italic |
| Strikethrough | ~~删除线~~ | Struck-through text |
| Bullet list | - 项目 | Bulleted list; nest by indenting |
| Numbered list | 1. 项目 | Auto-numbered list |
| Blockquote | > 引用 | A block with a left bar |
| Inline code | `code` | Monospaced inline snippet |
| Code block | ```语言 | Fenced block with language hint |
| Link | [文字](url) | A clickable hyperlink |
| Image |  | An embedded image |
| Horizontal rule | --- | A horizontal divider |
GitHub-Flavoured Extensions
| Feature | Syntax | Note |
|---|---|---|
| Table | | 列 A | 列 B | | --- | --- | | 1 | 2 | | The delimiter row controls alignment |
| Task list | - [x] 已完成 - [ ] 未完成 | An x inside the brackets marks it done |
| Autolink | https://example.com | A bare URL becomes a link automatically |
| Left align | | :--- | | A colon on the left of the delimiter row |
| Centre align | | :---: | | Colons on both sides |
| Right align | | ---: | | A colon on the right |
Frequently Asked Questions
What is the difference between Markdown and a rich-text editor?
The core difference is readability and control. Markdown is plain text with lightweight markup: it reads fine unrendered, opens in any editor, and suits version control naturally — Git shows a clean diff for every change, whereas rich text in binary or complex formats is nearly impossible to review. The cost is limited layout freedom; intricate text-and-image arrangements are out of reach. Rich text is WYSIWYG and powerful for layout, but content and styling are coupled, making migration and collaboration expensive. Markdown suits technical documentation, READMEs and blog drafts; rich text suits marketing pages and heavily designed material.
How do I control column alignment in a Markdown table?
Alignment is set by the delimiter row beneath the header. The default is left aligned; writing :--- left aligns explicitly; colons on both sides, :---:, centre the column; a colon on the right, ---:, right aligns it. The colon position maps directly onto the column, which makes it easy to remember. Two constraints: the delimiter row needs at least one hyphen, and its column count must match the header, otherwise the table is not recognised.
How do I get syntax highlighting in a code block?
Wrap the code in three backticks and put the language identifier immediately after the opening fence, such as ```python or ```javascript. That identifier tells the renderer which grammar to colour; omit or misspell it and you get a plain monospaced block. If the code itself contains backticks, use a longer fence — four backticks can safely wrap content containing three. For a single word or short expression, use a single pair of backticks for inline code instead.
Can Markdown be exported directly to PDF or Word?
Markdown is only a text format and has no export capability of its own, so a toolchain is required. The most common route converts to HTML and then prints or renders to PDF, which static site generators, editor plugins and command-line tools all handle; converting to Word usually means going through HTML or DOCX as an intermediate. The main difference is styling: default conversions look plain, and a good-looking PDF needs custom CSS. If the deliverable must be a beautifully typeset PDF, a layout tool may be less work than starting from Markdown.