4
<ul id="ProjectSubmenu">
5
<li><a href="/projects/markdown/" title="Markdown Project Page">Main</a></li>
6
<li><a href="/projects/markdown/basics" title="Markdown Basics">Basics</a></li>
7
<li><a class="selected" title="Markdown Syntax Documentation">Syntax</a></li>
8
<li><a href="/projects/markdown/license" title="Pricing and License Information">License</a></li>
9
<li><a href="/projects/markdown/dingus" title="Online Markdown Web Form">Dingus</a></li>
13
* [Overview](#overview)
14
* [Philosophy](#philosophy)
15
* [Inline HTML](#html)
16
* [Automatic Escaping for Special Characters](#autoescape)
17
* [Block Elements](#block)
18
* [Paragraphs and Line Breaks](#p)
20
* [Blockquotes](#blockquote)
22
* [Code Blocks](#precode)
23
* [Horizontal Rules](#hr)
24
* [Span Elements](#span)
29
* [Miscellaneous](#misc)
30
* [Backslash Escapes](#backslash)
31
* [Automatic Links](#autolink)
34
**Note:** This document is itself written using Markdown; you
35
can [see the source for it by adding '.text' to the URL][src].
37
[src]: /projects/markdown/syntax.text
41
<h2 id="overview">Overview</h2>
43
<h3 id="philosophy">Philosophy</h3>
45
Markdown is intended to be as easy-to-read and easy-to-write as is feasible.
47
Readability, however, is emphasized above all else. A Markdown-formatted
48
document should be publishable as-is, as plain text, without looking
49
like it's been marked up with tags or formatting instructions. While
50
Markdown's syntax has been influenced by several existing text-to-HTML
51
filters -- including [Setext] [1], [atx] [2], [Textile] [3], [reStructuredText] [4],
52
[Grutatext] [5], and [EtText] [6] -- the single biggest source of
53
inspiration for Markdown's syntax is the format of plain text email.
55
[1]: http://docutils.sourceforge.net/mirror/setext.html
56
[2]: http://www.aaronsw.com/2002/atx/
57
[3]: http://textism.com/tools/textile/
58
[4]: http://docutils.sourceforge.net/rst.html
59
[5]: http://www.triptico.com/software/grutatxt.html
60
[6]: http://ettext.taint.org/doc/
62
To this end, Markdown's syntax is comprised entirely of punctuation
63
characters, which punctuation characters have been carefully chosen so
64
as to look like what they mean. E.g., asterisks around a word actually
65
look like \*emphasis\*. Markdown lists look like, well, lists. Even
66
blockquotes look like quoted passages of text, assuming you've ever
71
<h3 id="html">Inline HTML</h3>
73
Markdown's syntax is intended for one purpose: to be used as a
74
format for *writing* for the web.
76
Markdown is not a replacement for HTML, or even close to it. Its
77
syntax is very small, corresponding only to a very small subset of
78
HTML tags. The idea is *not* to create a syntax that makes it easier
79
to insert HTML tags. In my opinion, HTML tags are already easy to
80
insert. The idea for Markdown is to make it easy to read, write, and
81
edit prose. HTML is a *publishing* format; Markdown is a *writing*
82
format. Thus, Markdown's formatting syntax only addresses issues that
83
can be conveyed in plain text.
85
For any markup that is not covered by Markdown's syntax, you simply
86
use HTML itself. There's no need to preface it or delimit it to
87
indicate that you're switching from Markdown to HTML; you just use
90
The only restrictions are that block-level HTML elements -- e.g. `<div>`,
91
`<table>`, `<pre>`, `<p>`, etc. -- must be separated from surrounding
92
content by blank lines, and the start and end tags of the block should
93
not be indented with tabs or spaces. Markdown is smart enough not
94
to add extra (unwanted) `<p>` tags around HTML block-level tags.
96
For example, to add an HTML table to a Markdown article:
98
This is a regular paragraph.
106
This is another regular paragraph.
108
Note that Markdown formatting syntax is not processed within block-level
109
HTML tags. E.g., you can't use Markdown-style `*emphasis*` inside an
112
Span-level HTML tags -- e.g. `<span>`, `<cite>`, or `<del>` -- can be
113
used anywhere in a Markdown paragraph, list item, or header. If you
114
want, you can even use HTML tags instead of Markdown formatting; e.g. if
115
you'd prefer to use HTML `<a>` or `<img>` tags instead of Markdown's
116
link or image syntax, go right ahead.
118
Unlike block-level HTML tags, Markdown syntax *is* processed within
122
<h3 id="autoescape">Automatic Escaping for Special Characters</h3>
124
In HTML, there are two characters that demand special treatment: `<`
125
and `&`. Left angle brackets are used to start tags; ampersands are
126
used to denote HTML entities. If you want to use them as literal
127
characters, you must escape them as entities, e.g. `<`, and
130
Ampersands in particular are bedeviling for web writers. If you want to
131
write about 'AT&T', you need to write '`AT&T`'. You even need to
132
escape ampersands within URLs. Thus, if you want to link to:
134
http://images.google.com/images?num=30&q=larry+bird
136
you need to encode the URL as:
138
http://images.google.com/images?num=30&q=larry+bird
140
in your anchor tag `href` attribute. Needless to say, this is easy to
141
forget, and is probably the single most common source of HTML validation
142
errors in otherwise well-marked-up web sites.
144
Markdown allows you to use these characters naturally, taking care of
145
all the necessary escaping for you. If you use an ampersand as part of
146
an HTML entity, it remains unchanged; otherwise it will be translated
149
So, if you want to include a copyright symbol in your article, you can write:
153
and Markdown will leave it alone. But if you write:
157
Markdown will translate it to:
161
Similarly, because Markdown supports [inline HTML](#html), if you use
162
angle brackets as delimiters for HTML tags, Markdown will treat them as
163
such. But if you write:
167
Markdown will translate it to:
171
However, inside Markdown code spans and blocks, angle brackets and
172
ampersands are *always* encoded automatically. This makes it easy to use
173
Markdown to write about HTML code. (As opposed to raw HTML, which is a
174
terrible format for writing about HTML syntax, because every single `<`
175
and `&` in your example code needs to be escaped.)
181
<h2 id="block">Block Elements</h2>
184
<h3 id="p">Paragraphs and Line Breaks</h3>
186
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.
191
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 `<br />` tag.
197
When you *do* want to insert a `<br />` break tag using Markdown, you
198
end a line with two or more spaces, then type return.
200
Yes, this takes a tad more effort to create a `<br />`, but a simplistic
201
"every line break is a `<br />`" rule wouldn't work for Markdown.
202
Markdown's email-style [blockquoting][bq] and multi-paragraph [list items][l]
203
work best -- and look better -- when you format them with hard breaks.
210
<h3 id="header">Headers</h3>
212
Markdown supports two styles of headers, [Setext] [1] and [atx] [2].
214
Setext-style headers are "underlined" using equal signs (for first-level
215
headers) and dashes (for second-level headers). For example:
223
Any number of underlining `=`'s or `-`'s will work.
225
Atx-style headers use 1-6 hash characters at the start of the line,
226
corresponding to header levels 1-6. For example:
234
Optionally, you may "close" atx-style headers. This is purely
235
cosmetic -- you can use this if you think it looks better. The
236
closing hashes don't even need to match the number of hashes
237
used to open the header. (The number of opening hashes
238
determines the header level.) :
244
### This is an H3 ######
247
<h3 id="blockquote">Blockquotes</h3>
249
Markdown uses email-style `>` characters for blockquoting. If you're
250
familiar with quoting passages of text in an email message, then you
251
know how to create a blockquote in Markdown. It looks best if you hard
252
wrap the text and put a `>` before every line:
254
> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
255
> consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
256
> Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
258
> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
259
> id sem consectetuer libero luctus adipiscing.
261
Markdown allows you to be lazy and only put the `>` before the first
262
line of a hard-wrapped paragraph:
264
> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
265
consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
266
Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
268
> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
269
id sem consectetuer libero luctus adipiscing.
271
Blockquotes can be nested (i.e. a blockquote-in-a-blockquote) by
272
adding additional levels of `>`:
274
> This is the first level of quoting.
276
> > This is nested blockquote.
278
> Back to the first level.
280
Blockquotes can contain other Markdown elements, including headers, lists,
283
> ## This is a header.
285
> 1. This is the first list item.
286
> 2. This is the second list item.
288
> Here's some example code:
290
> return shell_exec("echo $input | $markdown_script");
292
Any decent text editor should make email-style quoting easy. For
293
example, with BBEdit, you can make a selection and choose Increase
294
Quote Level from the Text menu.
297
<h3 id="list">Lists</h3>
299
Markdown supports ordered (numbered) and unordered (bulleted) lists.
301
Unordered lists use asterisks, pluses, and hyphens -- interchangably
320
Ordered lists use numbers followed by periods:
326
It's important to note that the actual numbers you use to mark the
327
list have no effect on the HTML output Markdown produces. The HTML
328
Markdown produces from the above list is:
336
If you instead wrote the list in Markdown like this:
348
you'd get the exact same HTML output. The point is, if you want to,
349
you can use ordinal numbers in your ordered Markdown lists, so that
350
the numbers in your source match the numbers in your published HTML.
351
But if you want to be lazy, you don't have to.
353
If you do use lazy list numbering, however, you should still start the
354
list with the number 1. At some point in the future, Markdown may support
355
starting ordered lists at an arbitrary number.
357
List markers typically start at the left margin, but may be indented by
358
up to three spaces. List markers must be followed by one or more spaces
361
To make lists look nice, you can wrap items with hanging indents:
363
* Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
364
Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi,
365
viverra nec, fringilla in, laoreet vitae, risus.
366
* Donec sit amet nisl. Aliquam semper ipsum sit amet velit.
367
Suspendisse id sem consectetuer libero luctus adipiscing.
369
But if you want to be lazy, you don't have to:
371
* Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
372
Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi,
373
viverra nec, fringilla in, laoreet vitae, risus.
374
* Donec sit amet nisl. Aliquam semper ipsum sit amet velit.
375
Suspendisse id sem consectetuer libero luctus adipiscing.
377
If list items are separated by blank lines, Markdown will wrap the
378
items in `<p>` tags in the HTML output. For example, this input:
400
<li><p>Magic</p></li>
403
List items may consist of multiple paragraphs. Each subsequent
404
paragraph in a list item must be intended by either 4 spaces
407
1. This is a list item with two paragraphs. Lorem ipsum dolor
408
sit amet, consectetuer adipiscing elit. Aliquam hendrerit
411
Vestibulum enim wisi, viverra nec, fringilla in, laoreet
412
vitae, risus. Donec sit amet nisl. Aliquam semper ipsum
415
2. Suspendisse id sem consectetuer libero luctus adipiscing.
417
It looks nice if you indent every line of the subsequent
418
paragraphs, but here again, Markdown will allow you to be
421
* This is a list item with two paragraphs.
423
This is the second paragraph in the list item. You're
424
only required to indent the first line. Lorem ipsum dolor
425
sit amet, consectetuer adipiscing elit.
427
* Another item in the same list.
429
To put a blockquote within a list item, the blockquote's `>`
430
delimiters need to be indented:
432
* A list item with a blockquote:
434
> This is a blockquote
435
> inside a list item.
437
To put a code block within a list item, the code block needs
438
to be indented *twice* -- 8 spaces or two tabs:
440
* A list item with a code block:
445
It's worth noting that it's possible to trigger an ordered list by
446
accident, by writing something like this:
448
1986. What a great season.
450
In other words, a *number-period-space* sequence at the beginning of a
451
line. To avoid this, you can backslash-escape the period:
453
1986\. What a great season.
457
<h3 id="precode">Code Blocks</h3>
459
Pre-formatted code blocks are used for writing about programming or
460
markup source code. Rather than forming normal paragraphs, the lines
461
of a code block are interpreted literally. Markdown wraps a code block
462
in both `<pre>` and `<code>` tags.
464
To produce a code block in Markdown, simply indent every line of the
465
block by at least 4 spaces or 1 tab. For example, given this input:
467
This is a normal paragraph:
469
This is a code block.
471
Markdown will generate:
473
<p>This is a normal paragraph:</p>
475
<pre><code>This is a code block.
478
One level of indentation -- 4 spaces or 1 tab -- is removed from each
479
line of the code block. For example, this:
481
Here is an example of AppleScript:
483
tell application "Foo"
489
<p>Here is an example of AppleScript:</p>
491
<pre><code>tell application "Foo"
496
A code block continues until it reaches a line that is not indented
497
(or the end of the article).
499
Within a code block, ampersands (`&`) and angle brackets (`<` and `>`)
500
are automatically converted into HTML entities. This makes it very
501
easy to include example HTML source code using Markdown -- just paste
502
it and indent it, and Markdown will handle the hassle of encoding the
503
ampersands and angle brackets. For example, this:
506
© 2004 Foo Corporation
511
<pre><code><div class="footer">
512
&copy; 2004 Foo Corporation
516
Regular Markdown syntax is not processed within code blocks. E.g.,
517
asterisks are just literal asterisks within a code block. This means
518
it's also easy to use Markdown to write about Markdown's own syntax.
522
<h3 id="hr">Horizontal Rules</h3>
524
You can produce a horizontal rule tag (`<hr />`) by placing three or
525
more hyphens, asterisks, or underscores on a line by themselves. If you
526
wish, you may use spaces between the hyphens or asterisks. Each of the
527
following lines will produce a horizontal rule:
537
---------------------------------------
544
<h2 id="span">Span Elements</h2>
546
<h3 id="link">Links</h3>
548
Markdown supports two style of links: *inline* and *reference*.
550
In both styles, the link text is delimited by [square brackets].
552
To create an inline link, use a set of regular parentheses immediately
553
after the link text's closing square bracket. Inside the parentheses,
554
put the URL where you want the link to point, along with an *optional*
555
title for the link, surrounded in quotes. For example:
557
This is [an example](http://example.com/ "Title") inline link.
559
[This link](http://example.net/) has no title attribute.
563
<p>This is <a href="http://example.com/" title="Title">
564
an example</a> inline link.</p>
566
<p><a href="http://example.net/">This link</a> has no
569
If you're referring to a local resource on the same server, you can
572
See my [About](/about/) page for details.
574
Reference-style links use a second set of square brackets, inside
575
which you place a label of your choosing to identify the link:
577
This is [an example][id] reference-style link.
579
You can optionally use a space to separate the sets of brackets:
581
This is [an example] [id] reference-style link.
583
Then, anywhere in the document, you define your link label like this,
586
[id]: http://example.com/ "Optional Title Here"
590
* Square brackets containing the link identifier (optionally
591
indented from the left margin using up to three spaces);
592
* followed by a colon;
593
* followed by one or more spaces (or tabs);
594
* followed by the URL for the link;
595
* optionally followed by a title attribute for the link, enclosed
596
in double or single quotes.
598
The link URL may, optionally, be surrounded by angle brackets:
600
[id]: <http://example.com/> "Optional Title Here"
602
You can put the title attribute on the next line and use extra spaces
603
or tabs for padding, which tends to look better with longer URLs:
605
[id]: http://example.com/longish/path/to/resource/here
606
"Optional Title Here"
608
Link definitions are only used for creating links during Markdown
609
processing, and are stripped from your document in the HTML output.
611
Link definition names may constist of letters, numbers, spaces, and punctuation -- but they are *not* case sensitive. E.g. these two links:
618
The *implicit link name* shortcut allows you to omit the name of the
619
link, in which case the link text itself is used as the name.
620
Just use an empty set of square brackets -- e.g., to link the word
621
"Google" to the google.com web site, you could simply write:
625
And then define the link:
627
[Google]: http://google.com/
629
Because link names may contain spaces, this shortcut even works for
630
multiple words in the link text:
632
Visit [Daring Fireball][] for more information.
634
And then define the link:
636
[Daring Fireball]: http://daringfireball.net/
638
Link definitions can be placed anywhere in your Markdown document. I
639
tend to put them immediately after each paragraph in which they're
640
used, but if you want, you can put them all at the end of your
641
document, sort of like footnotes.
643
Here's an example of reference links in action:
645
I get 10 times more traffic from [Google] [1] than from
646
[Yahoo] [2] or [MSN] [3].
648
[1]: http://google.com/ "Google"
649
[2]: http://search.yahoo.com/ "Yahoo Search"
650
[3]: http://search.msn.com/ "MSN Search"
652
Using the implicit link name shortcut, you could instead write:
654
I get 10 times more traffic from [Google][] than from
655
[Yahoo][] or [MSN][].
657
[google]: http://google.com/ "Google"
658
[yahoo]: http://search.yahoo.com/ "Yahoo Search"
659
[msn]: http://search.msn.com/ "MSN Search"
661
Both of the above examples will produce the following HTML output:
663
<p>I get 10 times more traffic from <a href="http://google.com/"
664
title="Google">Google</a> than from
665
<a href="http://search.yahoo.com/" title="Yahoo Search">Yahoo</a>
666
or <a href="http://search.msn.com/" title="MSN Search">MSN</a>.</p>
668
For comparison, here is the same paragraph written using
669
Markdown's inline link style:
671
I get 10 times more traffic from [Google](http://google.com/ "Google")
672
than from [Yahoo](http://search.yahoo.com/ "Yahoo Search") or
673
[MSN](http://search.msn.com/ "MSN Search").
675
The point of reference-style links is not that they're easier to
676
write. The point is that with reference-style links, your document
677
source is vastly more readable. Compare the above examples: using
678
reference-style links, the paragraph itself is only 81 characters
679
long; with inline-style links, it's 176 characters; and as raw HTML,
680
it's 234 characters. In the raw HTML, there's more markup than there
683
With Markdown's reference-style links, a source document much more
684
closely resembles the final output, as rendered in a browser. By
685
allowing you to move the markup-related metadata out of the paragraph,
686
you can add links without interrupting the narrative flow of your
690
<h3 id="em">Emphasis</h3>
692
Markdown treats asterisks (`*`) and underscores (`_`) as indicators of
693
emphasis. Text wrapped with one `*` or `_` will be wrapped with an
694
HTML `<em>` tag; double `*`'s or `_`'s will be wrapped with an HTML
695
`<strong>` tag. E.g., this input:
703
__double underscores__
707
<em>single asterisks</em>
709
<em>single underscores</em>
711
<strong>double asterisks</strong>
713
<strong>double underscores</strong>
715
You can use whichever style you prefer; the lone restriction is that
716
the same character must be used to open and close an emphasis span.
718
Emphasis can be used in the middle of a word:
720
un*fucking*believable
722
But if you surround an `*` or `_` with spaces, it'll be treated as a
723
literal asterisk or underscore.
725
To produce a literal asterisk or underscore at a position where it
726
would otherwise be used as an emphasis delimiter, you can backslash
729
\*this text is surrounded by literal asterisks\*
733
<h3 id="code">Code</h3>
735
To indicate a span of code, wrap it with backtick quotes (`` ` ``).
736
Unlike a pre-formatted code block, a code span indicates code within a
737
normal paragraph. For example:
739
Use the `printf()` function.
743
<p>Use the <code>printf()</code> function.</p>
745
To include a literal backtick character within a code span, you can use
746
multiple backticks as the opening and closing delimiters:
748
``There is a literal backtick (`) here.``
750
which will produce this:
752
<p><code>There is a literal backtick (`) here.</code></p>
754
The backtick delimiters surrounding a code span may include spaces --
755
one after the opening, one before the closing. This allows you to place
756
literal backtick characters at the beginning or end of a code span:
758
A single backtick in a code span: `` ` ``
760
A backtick-delimited string in a code span: `` `foo` ``
764
<p>A single backtick in a code span: <code>`</code></p>
766
<p>A backtick-delimited string in a code span: <code>`foo`</code></p>
768
With a code span, ampersands and angle brackets are encoded as HTML
769
entities automatically, which makes it easy to include example HTML
770
tags. Markdown will turn this:
772
Please don't use any `<blink>` tags.
776
<p>Please don't use any <code><blink></code> tags.</p>
780
`—` is the decimal-encoded equivalent of `—`.
784
<p><code>&#8212;</code> is the decimal-encoded
785
equivalent of <code>&mdash;</code>.</p>
789
<h3 id="img">Images</h3>
791
Admittedly, it's fairly difficult to devise a "natural" syntax for
792
placing images into a plain text document format.
794
Markdown uses an image syntax that is intended to resemble the syntax
795
for links, allowing for two styles: *inline* and *reference*.
797
Inline image syntax looks like this:
799
801
805
* An exclamation mark: `!`;
806
* followed by a set of square brackets, containing the `alt`
807
attribute text for the image;
808
* followed by a set of parentheses, containing the URL or path to
809
the image, and an optional `title` attribute enclosed in double
812
Reference-style image syntax looks like this:
816
Where "id" is the name of a defined image reference. Image references
817
are defined using syntax identical to link references:
819
[id]: url/to/image "Optional title attribute"
821
As of this writing, Markdown has no syntax for specifying the
822
dimensions of an image; if this is important to you, you can simply
823
use regular HTML `<img>` tags.
829
<h2 id="misc">Miscellaneous</h2>
831
<h3 id="autolink">Automatic Links</h3>
833
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:
835
<http://example.com/>
837
Markdown will turn this into:
839
<a href="http://example.com/">http://example.com/</a>
841
Automatic links for email addresses work similarly, except that
842
Markdown will also perform a bit of randomized decimal and hex
843
entity-encoding to help obscure your address from address-harvesting
844
spambots. For example, Markdown will turn this:
846
<address@example.com>
848
into something like this:
850
<a href="mailto:addre
851
ss@example.co
852
m">address@exa
853
mple.com</a>
855
which will render in a browser as a clickable link to "address@example.com".
857
(This sort of entity-encoding trick will indeed fool many, if not
858
most, address-harvesting bots, but it definitely won't fool all of
859
them. It's better than nothing, but an address published in this way
860
will probably eventually start receiving spam.)
864
<h3 id="backslash">Backslash Escapes</h3>
866
Markdown allows you to use backslash escapes to generate literal
867
characters which would otherwise have special meaning in Markdown's
868
formatting syntax. For example, if you wanted to surround a word with
869
literal asterisks (instead of an HTML `<em>` tag), you can backslashes
870
before the asterisks, like this:
872
\*literal asterisks\*
874
Markdown provides backslash escapes for the following characters:
885
- minus sign (hyphen)
added
removed
t/Text-MultiMarkdown.mdtest/Markdown_Documentation_-_Syntax.text
