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1−<h1>Markdown: Syntax</h1>
2−
3−<ul id="ProjectSubmenu">
4− <li><a href="/projects/markdown/" title="Markdown Project Page">Main</a></li>
5− <li><a href="/projects/markdown/basics" title="Markdown Basics">Basics</a></li>
6− <li><a class="selected" title="Markdown Syntax Documentation">Syntax</a></li>
7− <li><a href="/projects/markdown/license" title="Pricing and License Information">License</a></li>
8− <li><a href="/projects/markdown/dingus" title="Online Markdown Web Form">Dingus</a></li>
9−</ul>
10−
11−<ul>
12−<li><a href="#overview">Overview</a>
13−<ul>
14−<li><a href="#philosophy">Philosophy</a></li>
15−<li><a href="#html">Inline HTML</a></li>
16−<li><a href="#autoescape">Automatic Escaping for Special Characters</a></li>
17−</ul></li>
18−<li><a href="#block">Block Elements</a>
19−<ul>
20−<li><a href="#p">Paragraphs and Line Breaks</a></li>
21−<li><a href="#header">Headers</a></li>
22−<li><a href="#blockquote">Blockquotes</a></li>
23−<li><a href="#list">Lists</a></li>
24−<li><a href="#precode">Code Blocks</a></li>
25−<li><a href="#hr">Horizontal Rules</a></li>
26−</ul></li>
27−<li><a href="#span">Span Elements</a>
28−<ul>
29−<li><a href="#link">Links</a></li>
30−<li><a href="#em">Emphasis</a></li>
31−<li><a href="#code">Code</a></li>
32−<li><a href="#img">Images</a></li>
33−</ul></li>
34−<li><a href="#misc">Miscellaneous</a>
35−<ul>
36−<li><a href="#backslash">Backslash Escapes</a></li>
37−<li><a href="#autolink">Automatic Links</a></li>
38−</ul></li>
39−</ul>
40−
41−<p><strong>Note:</strong> This document is itself written using Markdown; you
42−can <a href="/projects/markdown/syntax.text">see the source for it by adding '.text' to the URL</a>.</p>
43−
44−<hr />
45−
46−<h2 id="overview">Overview</h2>
47−
48−<h3 id="philosophy">Philosophy</h3>
49−
50−<p>Markdown is intended to be as easy-to-read and easy-to-write as is feasible.</p>
51−
52−<p>Readability, however, is emphasized above all else. A Markdown-formatted
53−document should be publishable as-is, as plain text, without looking
54−like it's been marked up with tags or formatting instructions. While
55−Markdown's syntax has been influenced by several existing text-to-HTML
56−filters -- including <a href="http://docutils.sourceforge.net/mirror/setext.html">Setext</a>, <a href="http://www.aaronsw.com/2002/atx/">atx</a>, <a href="http://textism.com/tools/textile/">Textile</a>, <a href="http://docutils.sourceforge.net/rst.html">reStructuredText</a>,
57−<a href="http://www.triptico.com/software/grutatxt.html">Grutatext</a>, and <a href="http://ettext.taint.org/doc/">EtText</a> -- the single biggest source of
58−inspiration for Markdown's syntax is the format of plain text email.</p>
59−
60−<p>To this end, Markdown's syntax is comprised entirely of punctuation
61−characters, which punctuation characters have been carefully chosen so
62−as to look like what they mean. E.g., asterisks around a word actually
63−look like *emphasis*. Markdown lists look like, well, lists. Even
64−blockquotes look like quoted passages of text, assuming you've ever
65−used email.</p>
66−
67−<h3 id="html">Inline HTML</h3>
68−
69−<p>Markdown's syntax is intended for one purpose: to be used as a
70−format for <em>writing</em> for the web.</p>
71−
72−<p>Markdown is not a replacement for HTML, or even close to it. Its
73−syntax is very small, corresponding only to a very small subset of
74−HTML tags. The idea is <em>not</em> to create a syntax that makes it easier
75−to insert HTML tags. In my opinion, HTML tags are already easy to
76−insert. The idea for Markdown is to make it easy to read, write, and
77−edit prose. HTML is a <em>publishing</em> format; Markdown is a <em>writing</em>
78−format. Thus, Markdown's formatting syntax only addresses issues that
79−can be conveyed in plain text.</p>
80−
81−<p>For any markup that is not covered by Markdown's syntax, you simply
82−use HTML itself. There's no need to preface it or delimit it to
83−indicate that you're switching from Markdown to HTML; you just use
84−the tags.</p>
85−
86−<p>The only restrictions are that block-level HTML elements -- e.g. <code><div></code>,
87−<code><table></code>, <code><pre></code>, <code><p></code>, etc. -- must be separated from surrounding
88−content by blank lines, and the start and end tags of the block should
89−not be indented with tabs or spaces. Markdown is smart enough not
90−to add extra (unwanted) <code><p></code> tags around HTML block-level tags.</p>
91−
92−<p>For example, to add an HTML table to a Markdown article:</p>
93−
94−<pre><code>This is a regular paragraph.
95−
96−<table>
97− <tr>
98− <td>Foo</td>
99− </tr>
100−</table>
101−
102−This is another regular paragraph.
103−</code></pre>
104−
105−<p>Note that Markdown formatting syntax is not processed within block-level
106−HTML tags. E.g., you can't use Markdown-style <code>*emphasis*</code> inside an
107−HTML block.</p>
108−
109−<p>Span-level HTML tags -- e.g. <code><span></code>, <code><cite></code>, or <code><del></code> -- can be
110−used anywhere in a Markdown paragraph, list item, or header. If you
111−want, you can even use HTML tags instead of Markdown formatting; e.g. if
112−you'd prefer to use HTML <code><a></code> or <code><img></code> tags instead of Markdown's
113−link or image syntax, go right ahead.</p>
114−
115−<p>Unlike block-level HTML tags, Markdown syntax <em>is</em> processed within
116−span-level tags.</p>
117−
118−<h3 id="autoescape">Automatic Escaping for Special Characters</h3>
119−
120−<p>In HTML, there are two characters that demand special treatment: <code><</code>
121−and <code>&</code>. Left angle brackets are used to start tags; ampersands are
122−used to denote HTML entities. If you want to use them as literal
123−characters, you must escape them as entities, e.g. <code>&lt;</code>, and
124−<code>&amp;</code>.</p>
125−
126−<p>Ampersands in particular are bedeviling for web writers. If you want to
127−write about 'AT&T', you need to write '<code>AT&amp;T</code>'. You even need to
128−escape ampersands within URLs. Thus, if you want to link to:</p>
129−
130−<pre><code>http://images.google.com/images?num=30&q=larry+bird
131−</code></pre>
132−
133−<p>you need to encode the URL as:</p>
134−
135−<pre><code>http://images.google.com/images?num=30&amp;q=larry+bird
136−</code></pre>
137−
138−<p>in your anchor tag <code>href</code> attribute. Needless to say, this is easy to
139−forget, and is probably the single most common source of HTML validation
140−errors in otherwise well-marked-up web sites.</p>
141−
142−<p>Markdown allows you to use these characters naturally, taking care of
143−all the necessary escaping for you. If you use an ampersand as part of
144−an HTML entity, it remains unchanged; otherwise it will be translated
145−into <code>&amp;</code>.</p>
146−
147−<p>So, if you want to include a copyright symbol in your article, you can write:</p>
148−
149−<pre><code>&copy;
150−</code></pre>
151−
152−<p>and Markdown will leave it alone. But if you write:</p>
153−
154−<pre><code>AT&T
155−</code></pre>
156−
157−<p>Markdown will translate it to:</p>
158−
159−<pre><code>AT&amp;T
160−</code></pre>
161−
162−<p>Similarly, because Markdown supports <a href="#html">inline HTML</a>, if you use
163−angle brackets as delimiters for HTML tags, Markdown will treat them as
164−such. But if you write:</p>
165−
166−<pre><code>4 < 5
167−</code></pre>
168−
169−<p>Markdown will translate it to:</p>
170−
171−<pre><code>4 &lt; 5
172−</code></pre>
173−
174−<p>However, inside Markdown code spans and blocks, angle brackets and
175−ampersands are <em>always</em> encoded automatically. This makes it easy to use
176−Markdown to write about HTML code. (As opposed to raw HTML, which is a
177−terrible format for writing about HTML syntax, because every single <code><</code>
178−and <code>&</code> in your example code needs to be escaped.)</p>
179−
180−<hr />
181−
182−<h2 id="block">Block Elements</h2>
183−
184−<h3 id="p">Paragraphs and Line Breaks</h3>
185−
186−<p>A paragraph is simply one or more consecutive lines of text, separated
187−by one or more blank lines. (A blank line is any line that looks like a
188−blank line -- a line containing nothing but spaces or tabs is considered
189−blank.) Normal paragraphs should not be intended with spaces or tabs.</p>
190−
191−<p>The implication of the "one or more consecutive lines of text" rule is
192−that Markdown supports "hard-wrapped" text paragraphs. This differs
193−significantly from most other text-to-HTML formatters (including Movable
194−Type's "Convert Line Breaks" option) which translate every line break
195−character in a paragraph into a <code><br /></code> tag.</p>
196−
197−<p>When you <em>do</em> want to insert a <code><br /></code> break tag using Markdown, you
198−end a line with two or more spaces, then type return.</p>
199−
200−<p>Yes, this takes a tad more effort to create a <code><br /></code>, but a simplistic
201−"every line break is a <code><br /></code>" rule wouldn't work for Markdown.
202−Markdown's email-style <a href="#blockquote">blockquoting</a> and multi-paragraph <a href="#list">list items</a>
203−work best -- and look better -- when you format them with hard breaks.</p>
204−
205−<h3 id="header">Headers</h3>
206−
207−<p>Markdown supports two styles of headers, <a href="http://docutils.sourceforge.net/mirror/setext.html">Setext</a> and <a href="http://www.aaronsw.com/2002/atx/">atx</a>.</p>
208−
209−<p>Setext-style headers are "underlined" using equal signs (for first-level
210−headers) and dashes (for second-level headers). For example:</p>
211−
212−<pre><code>This is an H1
213−=============
214−
215−This is an H2
216−-------------
217−</code></pre>
218−
219−<p>Any number of underlining <code>=</code>'s or <code>-</code>'s will work.</p>
220−
221−<p>Atx-style headers use 1-6 hash characters at the start of the line,
222−corresponding to header levels 1-6. For example:</p>
223−
224−<pre><code># This is an H1
225−
226−## This is an H2
227−
228−###### This is an H6
229−</code></pre>
230−
231−<p>Optionally, you may "close" atx-style headers. This is purely
232−cosmetic -- you can use this if you think it looks better. The
233−closing hashes don't even need to match the number of hashes
234−used to open the header. (The number of opening hashes
235−determines the header level.) :</p>
236−
237−<pre><code># This is an H1 #
238−
239−## This is an H2 ##
240−
241−### This is an H3 ######
242−</code></pre>
243−
244−<h3 id="blockquote">Blockquotes</h3>
245−
246−<p>Markdown uses email-style <code>></code> characters for blockquoting. If you're
247−familiar with quoting passages of text in an email message, then you
248−know how to create a blockquote in Markdown. It looks best if you hard
249−wrap the text and put a <code>></code> before every line:</p>
250−
251−<pre><code>> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
252−> consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
253−> Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
254−>
255−> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
256−> id sem consectetuer libero luctus adipiscing.
257−</code></pre>
258−
259−<p>Markdown allows you to be lazy and only put the <code>></code> before the first
260−line of a hard-wrapped paragraph:</p>
261−
262−<pre><code>> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
263−consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
264−Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
265−
266−> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
267−id sem consectetuer libero luctus adipiscing.
268−</code></pre>
269−
270−<p>Blockquotes can be nested (i.e. a blockquote-in-a-blockquote) by
271−adding additional levels of <code>></code>:</p>
272−
273−<pre><code>> This is the first level of quoting.
274−>
275−> > This is nested blockquote.
276−>
277−> Back to the first level.
278−</code></pre>
279−
280−<p>Blockquotes can contain other Markdown elements, including headers, lists,
281−and code blocks:</p>
282−
283−<pre><code>> ## This is a header.
284−>
285−> 1. This is the first list item.
286−> 2. This is the second list item.
287−>
288−> Here's some example code:
289−>
290−> return shell_exec("echo $input | $markdown_script");
291−</code></pre>
292−
293−<p>Any decent text editor should make email-style quoting easy. For
294−example, with BBEdit, you can make a selection and choose Increase
295−Quote Level from the Text menu.</p>
296−
297−<h3 id="list">Lists</h3>
298−
299−<p>Markdown supports ordered (numbered) and unordered (bulleted) lists.</p>
300−
301−<p>Unordered lists use asterisks, pluses, and hyphens -- interchangably
302−-- as list markers:</p>
303−
304−<pre><code>* Red
305−* Green
306−* Blue
307−</code></pre>
308−
309−<p>is equivalent to:</p>
310−
311−<pre><code>+ Red
312−+ Green
313−+ Blue
314−</code></pre>
315−
316−<p>and:</p>
317−
318−<pre><code>- Red
319−- Green
320−- Blue
321−</code></pre>
322−
323−<p>Ordered lists use numbers followed by periods:</p>
324−
325−<pre><code>1. Bird
326−2. McHale
327−3. Parish
328−</code></pre>
329−
330−<p>It's important to note that the actual numbers you use to mark the
331−list have no effect on the HTML output Markdown produces. The HTML
332−Markdown produces from the above list is:</p>
333−
334−<pre><code><ol>
335−<li>Bird</li>
336−<li>McHale</li>
337−<li>Parish</li>
338−</ol>
339−</code></pre>
340−
341−<p>If you instead wrote the list in Markdown like this:</p>
342−
343−<pre><code>1. Bird
344−1. McHale
345−1. Parish
346−</code></pre>
347−
348−<p>or even:</p>
349−
350−<pre><code>3. Bird
351−1. McHale
352−8. Parish
353−</code></pre>
354−
355−<p>you'd get the exact same HTML output. The point is, if you want to,
356−you can use ordinal numbers in your ordered Markdown lists, so that
357−the numbers in your source match the numbers in your published HTML.
358−But if you want to be lazy, you don't have to.</p>
359−
360−<p>If you do use lazy list numbering, however, you should still start the
361−list with the number 1. At some point in the future, Markdown may support
362−starting ordered lists at an arbitrary number.</p>
363−
364−<p>List markers typically start at the left margin, but may be indented by
365−up to three spaces. List markers must be followed by one or more spaces
366−or a tab.</p>
367−
368−<p>To make lists look nice, you can wrap items with hanging indents:</p>
369−
370−<pre><code>* Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
371− Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi,
372− viverra nec, fringilla in, laoreet vitae, risus.
373−* Donec sit amet nisl. Aliquam semper ipsum sit amet velit.
374− Suspendisse id sem consectetuer libero luctus adipiscing.
375−</code></pre>
376−
377−<p>But if you want to be lazy, you don't have to:</p>
378−
379−<pre><code>* Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
380−Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi,
381−viverra nec, fringilla in, laoreet vitae, risus.
382−* Donec sit amet nisl. Aliquam semper ipsum sit amet velit.
383−Suspendisse id sem consectetuer libero luctus adipiscing.
384−</code></pre>
385−
386−<p>If list items are separated by blank lines, Markdown will wrap the
387−items in <code><p></code> tags in the HTML output. For example, this input:</p>
388−
389−<pre><code>* Bird
390−* Magic
391−</code></pre>
392−
393−<p>will turn into:</p>
394−
395−<pre><code><ul>
396−<li>Bird</li>
397−<li>Magic</li>
398−</ul>
399−</code></pre>
400−
401−<p>But this:</p>
402−
403−<pre><code>* Bird
404−
405−* Magic
406−</code></pre>
407−
408−<p>will turn into:</p>
409−
410−<pre><code><ul>
411−<li><p>Bird</p></li>
412−<li><p>Magic</p></li>
413−</ul>
414−</code></pre>
415−
416−<p>List items may consist of multiple paragraphs. Each subsequent
417−paragraph in a list item must be intended by either 4 spaces
418−or one tab:</p>
419−
420−<pre><code>1. This is a list item with two paragraphs. Lorem ipsum dolor
421− sit amet, consectetuer adipiscing elit. Aliquam hendrerit
422− mi posuere lectus.
423−
424− Vestibulum enim wisi, viverra nec, fringilla in, laoreet
425− vitae, risus. Donec sit amet nisl. Aliquam semper ipsum
426− sit amet velit.
427−
428−2. Suspendisse id sem consectetuer libero luctus adipiscing.
429−</code></pre>
430−
431−<p>It looks nice if you indent every line of the subsequent
432−paragraphs, but here again, Markdown will allow you to be
433−lazy:</p>
434−
435−<pre><code>* This is a list item with two paragraphs.
436−
437− This is the second paragraph in the list item. You're
438−only required to indent the first line. Lorem ipsum dolor
439−sit amet, consectetuer adipiscing elit.
440−
441−* Another item in the same list.
442−</code></pre>
443−
444−<p>To put a blockquote within a list item, the blockquote's <code>></code>
445−delimiters need to be indented:</p>
446−
447−<pre><code>* A list item with a blockquote:
448−
449− > This is a blockquote
450− > inside a list item.
451−</code></pre>
452−
453−<p>To put a code block within a list item, the code block needs
454−to be indented <em>twice</em> -- 8 spaces or two tabs:</p>
455−
456−<pre><code>* A list item with a code block:
457−
458− <code goes here>
459−</code></pre>
460−
461−<p>It's worth noting that it's possible to trigger an ordered list by
462−accident, by writing something like this:</p>
463−
464−<pre><code>1986. What a great season.
465−</code></pre>
466−
467−<p>In other words, a <em>number-period-space</em> sequence at the beginning of a
468−line. To avoid this, you can backslash-escape the period:</p>
469−
470−<pre><code>1986\. What a great season.
471−</code></pre>
472−
473−<h3 id="precode">Code Blocks</h3>
474−
475−<p>Pre-formatted code blocks are used for writing about programming or
476−markup source code. Rather than forming normal paragraphs, the lines
477−of a code block are interpreted literally. Markdown wraps a code block
478−in both <code><pre></code> and <code><code></code> tags.</p>
479−
480−<p>To produce a code block in Markdown, simply indent every line of the
481−block by at least 4 spaces or 1 tab. For example, given this input:</p>
482−
483−<pre><code>This is a normal paragraph:
484−
485− This is a code block.
486−</code></pre>
487−
488−<p>Markdown will generate:</p>
489−
490−<pre><code><p>This is a normal paragraph:</p>
491−
492−<pre><code>This is a code block.
493−</code></pre>
494−</code></pre>
495−
496−<p>One level of indentation -- 4 spaces or 1 tab -- is removed from each
497−line of the code block. For example, this:</p>
498−
499−<pre><code>Here is an example of AppleScript:
500−
501− tell application "Foo"
502− beep
503− end tell
504−</code></pre>
505−
506−<p>will turn into:</p>
507−
508−<pre><code><p>Here is an example of AppleScript:</p>
509−
510−<pre><code>tell application "Foo"
511− beep
512−end tell
513−</code></pre>
514−</code></pre>
515−
516−<p>A code block continues until it reaches a line that is not indented
517−(or the end of the article).</p>
518−
519−<p>Within a code block, ampersands (<code>&</code>) and angle brackets (<code><</code> and <code>></code>)
520−are automatically converted into HTML entities. This makes it very
521−easy to include example HTML source code using Markdown -- just paste
522−it and indent it, and Markdown will handle the hassle of encoding the
523−ampersands and angle brackets. For example, this:</p>
524−
525−<pre><code> <div class="footer">
526− &copy; 2004 Foo Corporation
527− </div>
528−</code></pre>
529−
530−<p>will turn into:</p>
531−
532−<pre><code><pre><code>&lt;div class="footer"&gt;
533− &amp;copy; 2004 Foo Corporation
534−&lt;/div&gt;
535−</code></pre>
536−</code></pre>
537−
538−<p>Regular Markdown syntax is not processed within code blocks. E.g.,
539−asterisks are just literal asterisks within a code block. This means
540−it's also easy to use Markdown to write about Markdown's own syntax.</p>
541−
542−<h3 id="hr">Horizontal Rules</h3>
543−
544−<p>You can produce a horizontal rule tag (<code><hr /></code>) by placing three or
545−more hyphens, asterisks, or underscores on a line by themselves. If you
546−wish, you may use spaces between the hyphens or asterisks. Each of the
547−following lines will produce a horizontal rule:</p>
548−
549−<pre><code>* * *
550−
551−***
552−
553−*****
554−
555−- - -
556−
557−---------------------------------------
558−
559−_ _ _
560−</code></pre>
561−
562−<hr />
563−
564−<h2 id="span">Span Elements</h2>
565−
566−<h3 id="link">Links</h3>
567−
568−<p>Markdown supports two style of links: <em>inline</em> and <em>reference</em>.</p>
569−
570−<p>In both styles, the link text is delimited by [square brackets].</p>
571−
572−<p>To create an inline link, use a set of regular parentheses immediately
573−after the link text's closing square bracket. Inside the parentheses,
574−put the URL where you want the link to point, along with an <em>optional</em>
575−title for the link, surrounded in quotes. For example:</p>
576−
577−<pre><code>This is [an example](http://example.com/ "Title") inline link.
578−
579−[This link](http://example.net/) has no title attribute.
580−</code></pre>
581−
582−<p>Will produce:</p>
583−
584−<pre><code><p>This is <a href="http://example.com/" title="Title">
585−an example</a> inline link.</p>
586−
587−<p><a href="http://example.net/">This link</a> has no
588−title attribute.</p>
589−</code></pre>
590−
591−<p>If you're referring to a local resource on the same server, you can
592−use relative paths:</p>
593−
594−<pre><code>See my [About](/about/) page for details.
595−</code></pre>
596−
597−<p>Reference-style links use a second set of square brackets, inside
598−which you place a label of your choosing to identify the link:</p>
599−
600−<pre><code>This is [an example][id] reference-style link.
601−</code></pre>
602−
603−<p>You can optionally use a space to separate the sets of brackets:</p>
604−
605−<pre><code>This is [an example] [id] reference-style link.
606−</code></pre>
607−
608−<p>Then, anywhere in the document, you define your link label like this,
609−on a line by itself:</p>
610−
611−<pre><code>[id]: http://example.com/ "Optional Title Here"
612−</code></pre>
613−
614−<p>That is:</p>
615−
616−<ul>
617−<li>Square brackets containing the link identifier (optionally
618−indented from the left margin using up to three spaces);</li>
619−<li>followed by a colon;</li>
620−<li>followed by one or more spaces (or tabs);</li>
621−<li>followed by the URL for the link;</li>
622−<li>optionally followed by a title attribute for the link, enclosed
623−in double or single quotes.</li>
624−</ul>
625−
626−<p>The link URL may, optionally, be surrounded by angle brackets:</p>
627−
628−<pre><code>[id]: <http://example.com/> "Optional Title Here"
629−</code></pre>
630−
631−<p>You can put the title attribute on the next line and use extra spaces
632−or tabs for padding, which tends to look better with longer URLs:</p>
633−
634−<pre><code>[id]: http://example.com/longish/path/to/resource/here
635− "Optional Title Here"
636−</code></pre>
637−
638−<p>Link definitions are only used for creating links during Markdown
639−processing, and are stripped from your document in the HTML output.</p>
640−
641−<p>Link definition names may constist of letters, numbers, spaces, and punctuation -- but they are <em>not</em> case sensitive. E.g. these two links:</p>
642−
643−<pre><code>[link text][a]
644−[link text][A]
645−</code></pre>
646−
647−<p>are equivalent.</p>
648−
649−<p>The <em>implicit link name</em> shortcut allows you to omit the name of the
650−link, in which case the link text itself is used as the name.
651−Just use an empty set of square brackets -- e.g., to link the word
652−"Google" to the google.com web site, you could simply write:</p>
653−
654−<pre><code>[Google][]
655−</code></pre>
656−
657−<p>And then define the link:</p>
658−
659−<pre><code>[Google]: http://google.com/
660−</code></pre>
661−
662−<p>Because link names may contain spaces, this shortcut even works for
663−multiple words in the link text:</p>
664−
665−<pre><code>Visit [Daring Fireball][] for more information.
666−</code></pre>
667−
668−<p>And then define the link:</p>
669−
670−<pre><code>[Daring Fireball]: http://daringfireball.net/
671−</code></pre>
672−
673−<p>Link definitions can be placed anywhere in your Markdown document. I
674−tend to put them immediately after each paragraph in which they're
675−used, but if you want, you can put them all at the end of your
676−document, sort of like footnotes.</p>
677−
678−<p>Here's an example of reference links in action:</p>
679−
680−<pre><code>I get 10 times more traffic from [Google] [1] than from
681−[Yahoo] [2] or [MSN] [3].
682−
683− [1]: http://google.com/ "Google"
684− [2]: http://search.yahoo.com/ "Yahoo Search"
685− [3]: http://search.msn.com/ "MSN Search"
686−</code></pre>
687−
688−<p>Using the implicit link name shortcut, you could instead write:</p>
689−
690−<pre><code>I get 10 times more traffic from [Google][] than from
691−[Yahoo][] or [MSN][].
692−
693− [google]: http://google.com/ "Google"
694− [yahoo]: http://search.yahoo.com/ "Yahoo Search"
695− [msn]: http://search.msn.com/ "MSN Search"
696−</code></pre>
697−
698−<p>Both of the above examples will produce the following HTML output:</p>
699−
700−<pre><code><p>I get 10 times more traffic from <a href="http://google.com/"
701−title="Google">Google</a> than from
702−<a href="http://search.yahoo.com/" title="Yahoo Search">Yahoo</a>
703−or <a href="http://search.msn.com/" title="MSN Search">MSN</a>.</p>
704−</code></pre>
705−
706−<p>For comparison, here is the same paragraph written using
707−Markdown's inline link style:</p>
708−
709−<pre><code>I get 10 times more traffic from [Google](http://google.com/ "Google")
710−than from [Yahoo](http://search.yahoo.com/ "Yahoo Search") or
711−[MSN](http://search.msn.com/ "MSN Search").
712−</code></pre>
713−
714−<p>The point of reference-style links is not that they're easier to
715−write. The point is that with reference-style links, your document
716−source is vastly more readable. Compare the above examples: using
717−reference-style links, the paragraph itself is only 81 characters
718−long; with inline-style links, it's 176 characters; and as raw HTML,
719−it's 234 characters. In the raw HTML, there's more markup than there
720−is text.</p>
721−
722−<p>With Markdown's reference-style links, a source document much more
723−closely resembles the final output, as rendered in a browser. By
724−allowing you to move the markup-related metadata out of the paragraph,
725−you can add links without interrupting the narrative flow of your
726−prose.</p>
727−
728−<h3 id="em">Emphasis</h3>
729−
730−<p>Markdown treats asterisks (<code>*</code>) and underscores (<code>_</code>) as indicators of
731−emphasis. Text wrapped with one <code>*</code> or <code>_</code> will be wrapped with an
732−HTML <code><em></code> tag; double <code>*</code>'s or <code>_</code>'s will be wrapped with an HTML
733−<code><strong></code> tag. E.g., this input:</p>
734−
735−<pre><code>*single asterisks*
736−
737−_single underscores_
738−
739−**double asterisks**
740−
741−__double underscores__
742−</code></pre>
743−
744−<p>will produce:</p>
745−
746−<pre><code><em>single asterisks</em>
747−
748−<em>single underscores</em>
749−
750−<strong>double asterisks</strong>
751−
752−<strong>double underscores</strong>
753−</code></pre>
754−
755−<p>You can use whichever style you prefer; the lone restriction is that
756−the same character must be used to open and close an emphasis span.</p>
757−
758−<p>Emphasis can be used in the middle of a word:</p>
759−
760−<pre><code>un*fucking*believable
761−</code></pre>
762−
763−<p>But if you surround an <code>*</code> or <code>_</code> with spaces, it'll be treated as a
764−literal asterisk or underscore.</p>
765−
766−<p>To produce a literal asterisk or underscore at a position where it
767−would otherwise be used as an emphasis delimiter, you can backslash
768−escape it:</p>
769−
770−<pre><code>\*this text is surrounded by literal asterisks\*
771−</code></pre>
772−
773−<h3 id="code">Code</h3>
774−
775−<p>To indicate a span of code, wrap it with backtick quotes (<code>`</code>).
776−Unlike a pre-formatted code block, a code span indicates code within a
777−normal paragraph. For example:</p>
778−
779−<pre><code>Use the `printf()` function.
780−</code></pre>
781−
782−<p>will produce:</p>
783−
784−<pre><code><p>Use the <code>printf()</code> function.</p>
785−</code></pre>
786−
787−<p>To include a literal backtick character within a code span, you can use
788−multiple backticks as the opening and closing delimiters:</p>
789−
790−<pre><code>``There is a literal backtick (`) here.``
791−</code></pre>
792−
793−<p>which will produce this:</p>
794−
795−<pre><code><p><code>There is a literal backtick (`) here.</code></p>
796−</code></pre>
797−
798−<p>The backtick delimiters surrounding a code span may include spaces --
799−one after the opening, one before the closing. This allows you to place
800−literal backtick characters at the beginning or end of a code span:</p>
801−
802−<pre><code>A single backtick in a code span: `` ` ``
803−
804−A backtick-delimited string in a code span: `` `foo` ``
805−</code></pre>
806−
807−<p>will produce:</p>
808−
809−<pre><code><p>A single backtick in a code span: <code>`</code></p>
810−
811−<p>A backtick-delimited string in a code span: <code>`foo`</code></p>
812−</code></pre>
813−
814−<p>With a code span, ampersands and angle brackets are encoded as HTML
815−entities automatically, which makes it easy to include example HTML
816−tags. Markdown will turn this:</p>
817−
818−<pre><code>Please don't use any `<blink>` tags.
819−</code></pre>
820−
821−<p>into:</p>
822−
823−<pre><code><p>Please don't use any <code>&lt;blink&gt;</code> tags.</p>
824−</code></pre>
825−
826−<p>You can write this:</p>
827−
828−<pre><code>`&#8212;` is the decimal-encoded equivalent of `&mdash;`.
829−</code></pre>
830−
831−<p>to produce:</p>
832−
833−<pre><code><p><code>&amp;#8212;</code> is the decimal-encoded
834−equivalent of <code>&amp;mdash;</code>.</p>
835−</code></pre>
836−
837−<h3 id="img">Images</h3>
838−
839−<p>Admittedly, it's fairly difficult to devise a "natural" syntax for
840−placing images into a plain text document format.</p>
841−
842−<p>Markdown uses an image syntax that is intended to resemble the syntax
843−for links, allowing for two styles: <em>inline</em> and <em>reference</em>.</p>
844−
845−<p>Inline image syntax looks like this:</p>
846−
847−<pre><code>
848−
849−
850−</code></pre>
851−
852−<p>That is:</p>
853−
854−<ul>
855−<li>An exclamation mark: <code>!</code>;</li>
856−<li>followed by a set of square brackets, containing the <code>alt</code>
857−attribute text for the image;</li>
858−<li>followed by a set of parentheses, containing the URL or path to
859−the image, and an optional <code>title</code> attribute enclosed in double
860−or single quotes.</li>
861−</ul>
862−
863−<p>Reference-style image syntax looks like this:</p>
864−
865−<pre><code>![Alt text][id]
866−</code></pre>
867−
868−<p>Where "id" is the name of a defined image reference. Image references
869−are defined using syntax identical to link references:</p>
870−
871−<pre><code>[id]: url/to/image "Optional title attribute"
872−</code></pre>
873−
874−<p>As of this writing, Markdown has no syntax for specifying the
875−dimensions of an image; if this is important to you, you can simply
876−use regular HTML <code><img></code> tags.</p>
877−
878−<hr />
879−
880−<h2 id="misc">Miscellaneous</h2>
881−
882−<h3 id="autolink">Automatic Links</h3>
883−
884−<p>Markdown supports a shortcut style for creating "automatic" links for URLs and email addresses: simply surround the URL or email address with angle brackets. What this means is that if you want to show the actual text of a URL or email address, and also have it be a clickable link, you can do this:</p>
885−
886−<pre><code><http://example.com/>
887−</code></pre>
888−
889−<p>Markdown will turn this into:</p>
890−
891−<pre><code><a href="http://example.com/">http://example.com/</a>
892−</code></pre>
893−
894−<p>Automatic links for email addresses work similarly, except that
895−Markdown will also perform a bit of randomized decimal and hex
896−entity-encoding to help obscure your address from address-harvesting
897−spambots. For example, Markdown will turn this:</p>
898−
899−<pre><code><address@example.com>
900−</code></pre>
901−
902−<p>into something like this:</p>
903−
904−<pre><code><a href="&#x6D;&#x61;i&#x6C;&#x74;&#x6F;:&#x61;&#x64;&#x64;&#x72;&#x65;
905−&#115;&#115;&#64;&#101;&#120;&#x61;&#109;&#x70;&#x6C;e&#x2E;&#99;&#111;
906−&#109;">&#x61;&#x64;&#x64;&#x72;&#x65;&#115;&#115;&#64;&#101;&#120;&#x61;
907−&#109;&#x70;&#x6C;e&#x2E;&#99;&#111;&#109;</a>
908−</code></pre>
909−
910−<p>which will render in a browser as a clickable link to "address@example.com".</p>
911−
912−<p>(This sort of entity-encoding trick will indeed fool many, if not
913−most, address-harvesting bots, but it definitely won't fool all of
914−them. It's better than nothing, but an address published in this way
915−will probably eventually start receiving spam.)</p>
916−
917−<h3 id="backslash">Backslash Escapes</h3>
918−
919−<p>Markdown allows you to use backslash escapes to generate literal
920−characters which would otherwise have special meaning in Markdown's
921−formatting syntax. For example, if you wanted to surround a word with
922−literal asterisks (instead of an HTML <code><em></code> tag), you can backslashes
923−before the asterisks, like this:</p>
924−
925−<pre><code>\*literal asterisks\*
926−</code></pre>
927−
928−<p>Markdown provides backslash escapes for the following characters:</p>
929−
930−<pre><code>\ backslash
931−` backtick
932−* asterisk
933−_ underscore
934−{} curly braces
935−[] square brackets
936−() parentheses
937−# hash mark
938−+ plus sign
939−- minus sign (hyphen)
940−. dot
941−! exclamation mark
942−</code></pre>