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<h1 id="markdown"><a class="header" href="#markdown">Markdown</a></h1>
<p>mdBook's <a href="https://github.com/raphlinus/pulldown-cmark">parser</a> adheres to the <a href="https://commonmark.org/">CommonMark</a> specification with some extensions described below.
You can take a quick <a href="https://commonmark.org/help/tutorial/">tutorial</a>,
or <a href="https://spec.commonmark.org/dingus/">try out</a> CommonMark in real time. A complete Markdown overview is out of scope for
this documentation, but below is a high level overview of some of the basics. For a more in-depth experience, check out the
<a href="https://www.markdownguide.org">Markdown Guide</a>.</p>
<h2 id="text-and-paragraphs"><a class="header" href="#text-and-paragraphs">Text and Paragraphs</a></h2>
<p>Text is rendered relatively predictably:</p>
<pre><code class="language-markdown">Here is a line of text.
This is a new line.
</code></pre>
<p>Will look like you might expect:</p>
<p>Here is a line of text.</p>
<p>This is a new line.</p>
<h2 id="headings"><a class="header" href="#headings">Headings</a></h2>
<p>Headings use the <code>#</code> marker and should be on a line by themselves. More <code>#</code> mean smaller headings:</p>
<pre><code class="language-markdown">### A heading
Some text.
#### A smaller heading
More text.
</code></pre>
<h3 id="a-heading"><a class="header" href="#a-heading">A heading</a></h3>
<p>Some text.</p>
<h4 id="a-smaller-heading"><a class="header" href="#a-smaller-heading">A smaller heading</a></h4>
<p>More text.</p>
<h2 id="lists"><a class="header" href="#lists">Lists</a></h2>
<p>Lists can be unordered or ordered. Ordered lists will order automatically:</p>
<pre><code class="language-markdown">* milk
* eggs
* butter
1. carrots
1. celery
1. radishes
</code></pre>
<ul>
<li>milk</li>
<li>eggs</li>
<li>butter</li>
</ul>
<ol>
<li>carrots</li>
<li>celery</li>
<li>radishes</li>
</ol>
<h2 id="links"><a class="header" href="#links">Links</a></h2>
<p>Linking to a URL or local file is easy:</p>
<pre><code class="language-markdown">Use [mdBook](https://github.com/rust-lang/mdBook).
Read about [mdBook](mdbook.md).
A bare url: &lt;https://www.rust-lang.org&gt;.
</code></pre>
<p>Use <a href="https://github.com/rust-lang/mdBook">mdBook</a>.</p>
<p>Read about <a href="mdbook.html">mdBook</a>.</p>
<p>A bare url: <a href="https://www.rust-lang.org">https://www.rust-lang.org</a>.</p>
<hr />
<p>Relative links that end with <code>.md</code> will be converted to the <code>.html</code> extension.
It is recommended to use <code>.md</code> links when possible.
This is useful when viewing the Markdown file outside of mdBook, for example on GitHub or GitLab which render Markdown automatically.</p>
<p>Links to <code>README.md</code> will be converted to <code>index.html</code>.
This is done since some services like GitHub render README files automatically, but web servers typically expect the root file to be called <code>index.html</code>.</p>
<p>You can link to individual headings with <code>#</code> fragments.
For example, <code>mdbook.md#text-and-paragraphs</code> would link to the <a href="#text-and-paragraphs">Text and Paragraphs</a> section above.
The ID is created by transforming the heading such as converting to lowercase and replacing spaces with dashes.
You can click on any heading and look at the URL in your browser to see what the fragment looks like.</p>
<h2 id="images"><a class="header" href="#images">Images</a></h2>
<p>Including images is simply a matter of including a link to them, much like in the <em>Links</em> section above. The following markdown
includes the Rust logo SVG image found in the <code>images</code> directory at the same level as this file:</p>
<pre><code class="language-markdown">![The Rust Logo](images/rust-logo-blk.svg)
</code></pre>
<p>Produces the following HTML when built with mdBook:</p>
<pre><code class="language-html">&lt;p&gt;&lt;img src="images/rust-logo-blk.svg" alt="The Rust Logo" /&gt;&lt;/p&gt;
</code></pre>
<p>Which, of course displays the image like so:</p>
<p><img src="images/rust-logo-blk.svg" alt="The Rust Logo" /></p>
<h2 id="extensions"><a class="header" href="#extensions">Extensions</a></h2>
<p>mdBook has several extensions beyond the standard CommonMark specification.</p>
<h3 id="strikethrough"><a class="header" href="#strikethrough">Strikethrough</a></h3>
<p>Text may be rendered with a horizontal line through the center by wrapping the
text with one or two tilde characters on each side:</p>
<pre><code class="language-text">An example of ~~strikethrough text~~.
</code></pre>
<p>This example will render as:</p>
<blockquote>
<p>An example of <del>strikethrough text</del>.</p>
</blockquote>
<p>This follows the <a href="https://github.github.com/gfm/#strikethrough-extension-">GitHub Strikethrough extension</a>.</p>
<h3 id="footnotes"><a class="header" href="#footnotes">Footnotes</a></h3>
<p>A footnote generates a small numbered link in the text which when clicked
takes the reader to the footnote text at the bottom of the item. The footnote
label is written similarly to a link reference with a caret at the front. The
footnote text is written like a link reference definition, with the text
following the label. Example:</p>
<pre><code class="language-text">This is an example of a footnote[^note].
[^note]: This text is the contents of the footnote, which will be rendered
towards the bottom.
</code></pre>
<p>This example will render as:</p>
<blockquote>
<p>This is an example of a footnote<sup class="footnote-reference"><a href="#note">1</a></sup>.</p>
<div class="footnote-definition" id="note"><sup class="footnote-definition-label">1</sup>
<p>This text is the contents of the footnote, which will be rendered
towards the bottom.</p>
</div>
</blockquote>
<p>The footnotes are automatically numbered based on the order the footnotes are
written.</p>
<h3 id="tables"><a class="header" href="#tables">Tables</a></h3>
<p>Tables can be written using pipes and dashes to draw the rows and columns of
the table. These will be translated to HTML table matching the shape. Example:</p>
<pre><code class="language-text">| Header1 | Header2 |
|---------|---------|
| abc | def |
</code></pre>
<p>This example will render similarly to this:</p>
<div class="table-wrapper"><table><thead><tr><th>Header1</th><th>Header2</th></tr></thead><tbody>
<tr><td>abc</td><td>def</td></tr>
</tbody></table>
</div>
<p>See the specification for the <a href="https://github.github.com/gfm/#tables-extension-">GitHub Tables extension</a> for more
details on the exact syntax supported.</p>
<h3 id="task-lists"><a class="header" href="#task-lists">Task lists</a></h3>
<p>Task lists can be used as a checklist of items that have been completed.
Example:</p>
<pre><code class="language-md">- [x] Complete task
- [ ] Incomplete task
</code></pre>
<p>This will render as:</p>
<blockquote>
<ul>
<li><input disabled="" type="checkbox" checked=""/>
Complete task</li>
<li><input disabled="" type="checkbox"/>
Incomplete task</li>
</ul>
</blockquote>
<p>See the specification for the <a href="https://github.github.com/gfm/#task-list-items-extension-">task list extension</a> for more details.</p>
<h3 id="smart-punctuation"><a class="header" href="#smart-punctuation">Smart punctuation</a></h3>
<p>Some ASCII punctuation sequences will be automatically turned into fancy Unicode
characters:</p>
<div class="table-wrapper"><table><thead><tr><th>ASCII sequence</th><th>Unicode</th></tr></thead><tbody>
<tr><td><code>--</code></td><td></td></tr>
<tr><td><code>---</code></td><td></td></tr>
<tr><td><code>...</code></td><td></td></tr>
<tr><td><code>"</code></td><td>“ or ”, depending on context</td></tr>
<tr><td><code>'</code></td><td> or , depending on context</td></tr>
</tbody></table>
</div>
<p>So, no need to manually enter those Unicode characters!</p>
<p>This feature is disabled by default.
To enable it, see the <a href="configuration/renderers.html#html-renderer-options"><code>output.html.curly-quotes</code></a> config option.</p>
<h3 id="heading-attributes"><a class="header" href="#heading-attributes">Heading attributes</a></h3>
<p>Headings can have a custom HTML ID and classes. This lets you maintain the same ID even if you change the heading's text, it also lets you add multiple classes in the heading.</p>
<p>Example:</p>
<pre><code class="language-md"># Example heading { #first .class1 .class2 }
</code></pre>
<p>This makes the level 1 heading with the content <code>Example heading</code>, ID <code>first</code>, and classes <code>class1</code> and <code>class2</code>. Note that the attributes should be space-separated.</p>
<p>More information can be found in the <a href="https://github.com/raphlinus/pulldown-cmark/blob/master/pulldown-cmark/specs/heading_attrs.txt">heading attrs spec page</a>.</p>
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