Markdown
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Mardown Main
Go toMarkdown is a text-to-HTML conversion tool for web writers.
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Projects
Go toMarkdown, plugins, command-line tools and services.
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Basics
Go toPage offers a brief overview of what it’s like to use Markdown.
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Syntax
Go toMarkdown is
intendedto be as easy-to-read and easy-to-write as is feasible. -
License
Go toMarkdown is free software, available under the terms of a BSD-style open source license.
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Dingus
Go toMD 1.0.2b7 / SmartyPants 1.6.1b9: © 2004–2026 John Gruber
Download⚓︎
Download
Markdown 1.0.1 (18 KB) — 17 Dec 2004
Introduction⚓︎
Introduction
Markdown is a text-to-HTML conversion tool for web writers. Markdown allows you to write using an easy-to-read, easy-to-write plain text format, then convert it to structurally valid HTML.
Thus, “Markdown” is two things: (1) a plain text formatting syntax; and (2) a software tool, written in Perl, that converts the plain text formatting to HTML.
See the Syntax page for details pertaining to Markdown’s formatting syntax. You can try it out, right now, using the online Dingus.
The overriding design goal for Markdown’s formatting syntax is to make it as readable as possible. The idea is that a Markdown-formatted document should be publishable as-is, as plain text, without looking like it’s been marked up with tags or formatting instructions. While Markdown’s syntax has been influenced by several existing text-to-HTML filters, the single biggest source of inspiration for Markdown’s syntax is the format of plain text email.
The best way to get a feel for Markdown’s formatting syntax is simply to look at a Markdown-formatted document. For example, you can view the Markdown source for the article text on this page here: http://daringfireball.net/projects/markdown/index.text
(You can use this ‘.text’ suffix trick to view the Markdown source for the content of each of the pages in this section, e.g. the Syntax and License pages.)
Markdown is free software, available under a BSD-style open source license.
See the License page for more information.
Discussion List⚓︎
Discussion List
I’ve set up a public mailing list for discussion about Markdown. Any topic related to Markdown — both its formatting syntax and its software — is fair game for discussion. Anyone who is interested is welcome to join.
It’s my hope that the mailing list will lead to good ideas for future improvements to Markdown.
Installation and Requirements⚓︎
Installation and Requirements
Markdown requires Perl 5.6.0 or later. Welcome to the 21st Century.
Markdown also requires the standard Perl library module Digest::MD5, which is probably already installed on your server.
Movable Type⚓︎
Movable Type
Markdown works with Movable Type version 2.6 or later (including Movable Type 3.0).
1 ] Copy the “Markdown.pl” file into your Movable Type “plugins” directory. The “plugins” directory should be in the same directory as “mt.cgi”; if the “plugins” directory doesn’t already exist, use your FTP program to create it. Your installation should look like this:
2 ] Once installed, Markdown will appear as an option in Movable Type’s Text Formatting pop-up menu. This is selectable on a per-post basis:
Markdown translates your posts to HTML when you publish; the posts themselves are stored in your MT database in Markdown format.
3 ] If you also install SmartyPants 1.5 (or later), Markdown will offer a second text formatting option: “Markdown With SmartyPants”. This option is the same as the regular “Markdown” formatter, except that it automatically uses SmartyPants to create typographically correct curly quotes, em-dashes, and ellipses. See the SmartyPants web page for more information.
4 ] To make Markdown (or “Markdown With SmartyPants”) your default text formatting option for new posts, go to Weblog Config: Preferences.
Note that by default, Markdown produces XHTML output. To configure Markdown to produce HTML 4 output, see “Configuration”, below.
Blosxom⚓︎
Blosxom
Markdown works with Blosxom version 2.0 or later.
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Rename the “Markdown.pl” plug-in to “Markdown” (case is important). Movable Type requires plug-ins to have a “.pl” extension; Blosxom forbids it.
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Copy the “Markdown” plug-in file to your Blosxom plug-ins folder. If you’re not sure where your Blosxom plug-ins folder is, see the Blosxom documentation for information.
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That’s it. The entries in your weblog will now automatically be processed by Markdown.
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If you’d like to apply Markdown formatting only to certain posts, rather than all of them, Markdown can optionally be used in conjunction with Blosxom’s Meta plug-in. First, install the Meta plug-in. Next, open the Markdown plug-in file in a text editor, and set the configuration variable
$g_blosxom_use_metato 1. Then, simply include a “meta-markup: Markdown” header line at the top of each post you compose using Markdown.
BBEdit⚓︎
BBEdit
Markdown works with BBEdit 6.1 or later on Mac OS X. It also works with BBEdit 5.1 or later and MacPerl 5.6.1 on Mac OS 8.6 or later. If you’re running Mac OS X 10.2 (Jaguar), you may need to install the Perl module Digest::MD5 from CPAN; Digest::MD5 comes pre-installed on Mac OS X 10.3 (Panther).
1 ] Copy the “Markdown.pl” file to appropriate filters folder in your “BBEdit Support” folder. On Mac OS X, this should be:
See the BBEdit documentation for more details on the location of these folders.
You can rename “Markdown.pl” to whatever you wish.
2 ] That’s it. To use Markdown, select some text in a BBEdit document, then choose Markdown from the Filters sub-menu in the “#!” menu, or the Filters floating palette
Configuration⚓︎
Configuration
By default, Markdown produces XHTML-style output for tags with empty elements. E.g.:
Markdown can be configured to produce HTML-style tags; e.g.:
Movable Type⚓︎
Movable Type
You need to use a special MTMarkdownOptions container tag in each Movable Type template where you want HTML 4-style output:
The easiest way to use MTMarkdownOptions is probably to put the opening tag right after your <body> tag, and the closing tag right before </body>.
To suppress Markdown processing in a particular template, i.e. to publish the raw Markdown-formatted text without translation into (X)HTML, set the output attribute to ‘raw’:
Command-Line⚓︎
Command-Line
Use the --html4tags command-line switch to produce HTML output from a Unix-style command line. E.g.:
Type perldoc Markdown.pl, or read the POD documentation within the Markdown.pl source code for more information.
Acknowledgements⚓︎
Acknowledgements
Aaron Swartz deserves a tremendous amount of credit for his feedback on the design of Markdown’s formatting syntax. Markdown is much better thanks to Aaron’s ideas, feedback, and testing. Also, Aaron’s html2text is a very handy (and free) utility for turning HTML into Markdown-formatted plain text.
Nathaniel Irons, Dan Benjamin, Daniel Bogan, and Jason Perkins also deserve thanks for their feedback.
Michel Fortin has ported Markdown to PHP; it’s a splendid port, and highly recommended for anyone looking for a PHP implementation of Markdown.
Getting the Gist of Markdown’s Formatting Syntax⚓︎
Getting the Gist of Markdown’s Formatting Syntax
This page offers a brief overview of what it’s like to use Markdown. The syntax page provides complete, detailed documentation for every feature, but Markdown should be very easy to pick up simply by looking at a few examples of it in action. The examples on this page are written in a before/after style, showing example syntax and the HTML output produced by Markdown.
It’s also helpful to simply try Markdown out; the Dingus is a web application that allows you type your own Markdown-formatted text and translate it to XHTML.
Note!
This document is itself written using Markdown; you can see the source for it by adding ‘.text’ to the URL.
Paragraphs, Headers, Blockquotes⚓︎
Paragraphs, Headers, Blockquotes
A paragraph is simply one or more consecutive lines of text, separated by one or more blank lines. (A blank line is any line that looks like a blank line — a line containing nothing but spaces or tabs is considered blank.) Normal paragraphs should not be indented with spaces or tabs.
Markdown offers two styles of headers: Setext and atx. Setext-style headers for <h1> and <h2> are created by “underlining” with equal signs (=) and hyphens (-), respectively. To create an atx-style header, you put 1-6 hash marks (#) at the beginning of the line — the number of hashes equals the resulting HTML header level.
Markdown / Output
Blockquotes are indicated using email-style ‘>’ angle brackets.
Markdown:
A First Level Header
====================
A Second Level Header
---------------------
Now is the time for all good men to come to
the aid of their country. This is just a
regular paragraph.
The quick brown fox jumped over the lazy
dog's back.
### Header 3
> This is a blockquote.
>
> This is the second paragraph in the blockquote.
>
> ## This is an H2 in a blockquote
Output:
<h1>A First Level Header</h1>
<h2>A Second Level Header</h2>
<p>Now is the time for all good men to come to
the aid of their country. This is just a
regular paragraph.</p>
<p>The quick brown fox jumped over the lazy
dog's back.</p>
<h3>Header 3</h3>
<blockquote>
<p>This is a blockquote.</p>
<p>This is the second paragraph in the blockquote.</p>
<h2>This is an H2 in a blockquote</h2>
</blockquote>
Phrase Emphasis⚓︎
Phrase Emphasis
Markdown uses asterisks and underscores to indicate spans of emphasis.
Markdown:
Some of these words *are emphasized*.
Some of these words _are emphasized also_.
Use two asterisks for **strong emphasis**.
Or, if you prefer, __use two underscores instead__.
Output:
Lists⚓︎
Lists
Unordered (bulleted) lists use asterisks, pluses, and hyphens (*, +, and -) as list markers. These three markers are interchangable; this:
this:
and this:
all produce the same output:
Ordered (numbered) lists use regular numbers, followed by periods, as list markers:
Output:
If you put blank lines between items, you’ll get <p> tags for the list item text. You can create multi-paragraph list items by indenting the paragraphs by 4 spaces or 1 tab:
Output:
Links⚓︎
Links
Markdown supports two styles for creating links: inline and reference. With both styles, you use square brackets to delimit the text you want to turn into a link.
Inline-style links use parentheses immediately after the link text. For example:
Output:
Optionally, you may include a title attribute in the parentheses:
Output:
Reference-style links allow you to refer to your links by names, which you define elsewhere in your document:
I get 10 times more traffic from [Google][1] than from
[Yahoo][2] or [MSN][3].
[1]: http://google.com "Google"
[2]: http://yahoo.com "Yahoo Search"
[3]: http://msn.com "MSN Search"
Output:
<p>I get 10 times more traffic from <a href="http://google.com"
title="Google">Google</a> than from <a href="http://yahoo.com"
title="Yahoo Search">Yahoo</a> or <a href="http://msn.com"
title="MSN Search">MSN</a>.</p>
The title attribute is optional. Link names may contain letters, numbers and spaces, but are not case sensitive:
I start my morning with a cup of coffee and
[The New York Times][NY Times].
[ny times]: http://nytimes.com
Output:
Images⚓︎
Images
Image syntax is very much like link syntax.
Inline (titles are optional):
Reference-style:
Both of the above examples produce the same output:
Code⚓︎
Code
In a regular paragraph, you can create code span by wrapping text in backtick quotes. Any ampersands (&) and angle brackets (< or >) will automatically be translated into HTML entities. This makes it easy to use Markdown to write about HTML example code:
I strongly recommend against using any `<blink>` tags.
I wish SmartyPants used named entities like `—`
instead of decimal-encoded entities like `—`.
Output:
<p>I strongly recommend against using any
<code><blink></code> tags.</p>
<p>I wish SmartyPants used named entities like
<code>—</code> instead of decimal-encoded
entities like <code>—</code>.</p>
To specify an entire block of pre-formatted code, indent every line of the block by 4 spaces or 1 tab. Just like with code spans, &, <, and > characters will be escaped automatically.
Markdown:
If you want your page to validate under XHTML 1.0 Strict,
you've got to put paragraph tags in your blockquotes:
<blockquote>
<p>For example.</p>
</blockquote>
Output:
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Overview
Go toMarkdown is intended to be as easy-to-read and easy-to-write is feasible.
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Philosophy
Go toReadability, however, is emphasized above all else, should be publishable as-is.
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Inline HTML
Go toMarkdown is not a replacement for HTML, or even close to it. Syntax is very small.
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Auto Esc SPC
Go toIn HTML, there are two chars that demand special treatment: < and &.
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Block Elements
Go toA para is simply one or more consec lines of text, separated by one or more blank lines.
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Paras and Line Breaks
Go toA paragraph is simply one or more consecutive lines of text.
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Headers
Go toMarkdown supports two styles of headers, Setext and atx.
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Blockquotes
Go toMarkdown uses email-style > characters for blockquoting.
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Lists
Go toMarkdown supports ordered (numbered) and unordered (bulleted) lists.
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Code Blocks
Go toPre-formatted code blocks are used for writing about prog. or markup source code.
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Horizontal Rules
Go toProd horiz rule tag
(<hr />)by placing three or more hyphens, asterisks., or_'son a line. -
Span Elements
Go toMD supports two styles of links: inline and ref, link text is delimited by [square brackets].
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Links
Go toMD supports two styles of links: inline and ref, link text is delimited by [square brackets].
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Emphasis
Go toMarkdown treats asterisks (*) and underscores (_) as indicators of emphasis.
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Code
Go toTo indicate a span of code, wrap it with backtick quotes (`).
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Images
Go toIt’s difficult to devise a “natural” syntax for placing images into a plain text doc format.
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Miscellaneous
Go toMD supports a shortcut style for creating “auto” links for URLs and email addresses
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Backslash Escapes
Go toMarkdown allows you to use backslash escapes to generate literal characters
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Automatic Links
Go toMD supports a shortcut style for creating “auto” links for URLs and email addresses.
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BBColors (v1.0.1)
Go toFree cmd-line tool: Save/load txt colour pref schs. for BBEdit and TextWrangler.
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SmartyPants (v1.5.1)
Go toSmartyPants is a free web publishing plug-in for Movable Type, Blosxom, and BBEdit.
Note!
This document is itself written using Markdown; you can see the source for it by adding ‘.text’ to the URL.
Overview⚓︎
Philosophy⚓︎
Philosophy
Markdown is intended to be as easy-to-read and easy-to-write as is feasible.
Readability, however, is emphasized above all else. A Markdown-formatted document should be publishable as-is, as plain text, without looking like it’s been marked up with tags or formatting instructions. While Markdown’s syntax has been influenced by several existing text-to-HTML filters — including Setext, atx, Textile, reStructuredText, Grutatext, and EtText — the single biggest source of inspiration for Markdown’s syntax is the format of plain text email.
To this end, Markdown’s syntax is comprised entirely of punctuation characters, which punctuation characters have been carefully chosen so as to look like what they mean. E.g., asterisks around a word actually look like emphasis. Markdown lists look like, well, lists. Even blockquotes look like quoted passages of text, assuming you’ve ever used email.
Inline HTML⚓︎
Inline HTML
Markdown’s syntax is intended for one purpose: to be used as a format for writing for the web.
Markdown is not a replacement for HTML, or even close to it. Its syntax is very small, corresponding only to a very small subset of HTML tags. The idea is not to create a syntax that makes it easier to insert HTML tags. In my opinion, HTML tags are already easy to insert. The idea for Markdown is to make it easy to read, write, and edit prose. HTML is a publishing format; Markdown is a writing format. Thus, Markdown’s formatting syntax only addresses issues that can be conveyed in plain text.
For any markup that is not covered by Markdown’s syntax, you simply use HTML itself. There’s no need to preface it or delimit it to indicate that you’re switching from Markdown to HTML; you just use the tags.
The only restrictions are that block-level HTML elements — e.g. <div>, <table>, <pre>, <p>, etc. — must be separated from surrounding content by blank lines, and the start and end tags of the block should not be indented with tabs or spaces. Markdown is smart enough not to add extra (unwanted) <p> tags around HTML block-level tags.
For example, to add an HTML table to a Markdown article:
This is a regular paragraph.
<table>
<tr>
<td>Foo</td>
</tr>
</table>
This is another regular paragraph.
Note that Markdown formatting syntax is not processed within block-level HTML tags. E.g., you can’t use Markdown-style *emphasis* inside an HTML block.
Span-level HTML tags — e.g. <span>, <cite>, or <del> — can be used anywhere in a Markdown paragraph, list item, or header. If you want, you can even use HTML tags instead of Markdown formatting; e.g. if you’d prefer to use HTML <a> or <img> tags instead of Markdown’s link or image syntax, go right ahead.
Unlike block-level HTML tags, Markdown syntax is processed within span-level tags.
Automatic Escaping for Special Characters⚓︎
Automatic Escaping for Special Characters
In HTML, there are two characters that demand special treatment: < and &. Left angle brackets are used to start tags; ampersands are used to denote HTML entities. If you want to use them as literal characters, you must escape them as entities, e.g. <, and &.
Ampersands in particular are bedeviling for web writers. If you want to write about ‘AT&T’, you need to write ‘AT&T’. You even need to escape ampersands within URLs. Thus, if you want to link to:
you need to encode the URL as:
in your anchor tag href attribute. Needless to say, this is easy to forget, and is probably the single most common source of HTML validation errors in otherwise well-marked-up web sites.
Markdown allows you to use these characters naturally, taking care of all the necessary escaping for you. If you use an ampersand as part of an HTML entity, it remains unchanged; otherwise it will be translated into &.
So, if you want to include a copyright symbol in your article, you can write:
and Markdown will leave it alone. But if you write:
Markdown will translate it to:
Similarly, because Markdown supports inline HTML, if you use angle brackets as delimiters for HTML tags, Markdown will treat them as such. But if you write:
Markdown will translate it to:
However, inside Markdown code spans and blocks, angle brackets and ampersands are always encoded automatically. This makes it easy to use Markdown to write about HTML code. (As opposed to raw HTML, which is a terrible format for writing about HTML syntax, because every single < and & in your example code needs to be escaped.)
Block Elements⚓︎
Paragraphs and Line Breaks⚓︎
Paragraphs and Line Breaks
A paragraph is simply one or more consecutive lines of text, separated by one or more blank lines. (A blank line is any line that looks like a blank line — a line containing nothing but spaces or tabs is considered blank.) Normal paragraphs should not be indented with spaces or tabs.
The implication of the “one or more consecutive lines of text” rule is that Markdown supports “hard-wrapped” text paragraphs. This differs significantly from most other text-to-HTML formatters (including Movable Type’s “Convert Line Breaks” option) which translate every line break character in a paragraph into a <br /> tag.
When you do want to insert a <br /> break tag using Markdown, you end a line with two or more spaces, then type return.
Yes, this takes a tad more effort to create a <br />, but a simplistic “every line break is a <br />” rule wouldn’t work for Markdown. Markdown’s email-style blockquoting and multi-paragraph list items work best — and look better — when you format them with hard breaks.
Headers⚓︎
Headers
Markdown supports two styles of headers, Setext and atx.
Setext-style headers are “underlined” using equal signs (for first-level headers) and dashes (for second-level headers). For example:
Any number of underlining =’s or -’s will work.
Atx-style headers use 1-6 hash characters at the start of the line, corresponding to header levels 1-6. For example:
Optionally, you may “close” atx-style headers. This is purely cosmetic — you can use this if you think it looks better. The closing hashes don’t even need to match the number of hashes used to open the header. (The number of opening hashes determines the header level.) :
Blockquotes⚓︎
Blockquotes
Markdown uses email-style > characters for blockquoting. If you’re familiar with quoting passages of text in an email message, then you know how to create a blockquote in Markdown. It looks best if you hard wrap the text and put a > before every line:
> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
> consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
> Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
>
> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
> id sem consectetuer libero luctus adipiscing.
Markdown allows you to be lazy and only put the > before the first line of a hard-wrapped paragraph:
> This is a blockquote with two paragraphs. Lorem ipsum dolor sit amet,
consectetuer adipiscing elit. Aliquam hendrerit mi posuere lectus.
Vestibulum enim wisi, viverra nec, fringilla in, laoreet vitae, risus.
> Donec sit amet nisl. Aliquam semper ipsum sit amet velit. Suspendisse
id sem consectetuer libero luctus adipiscing.
Blockquotes can be nested (i.e. a blockquote-in-a-blockquote) by adding additional levels of >:
Blockquotes can contain other Markdown elements, including headers, lists, and code blocks:
> ## This is a header.
>
> 1. This is the first list item.
> 2. This is the second list item.
>
> Here's some example code:
>
> return shell_exec("echo $input | $markdown_script");
Any decent text editor should make email-style quoting easy. For example, with BBEdit, you can make a selection and choose Increase Quote Level from the Text menu.
Lists⚓︎
Lists
Markdown supports ordered (numbered) and unordered (bulleted) lists.
Unordered lists use asterisks, pluses, and hyphens — interchangably — as list markers:
is equivalent to:
and:
Ordered lists use numbers followed by periods:
It’s important to note that the actual numbers you use to mark the list have no effect on the HTML output Markdown produces. If you instead wrote the list in Markdown like this:
you’d get the exact same HTML output. The point is, if you want to, you can use ordinal numbers in your ordered Markdown lists, so that the numbers in your source match the numbers in your published HTML. But if you want to be lazy, you don’t have to.
List markers typically start at the left margin, but may be indented by up to three spaces. List markers must be followed by one or more spaces or a tab.
To make lists look nice, you can wrap items with hanging indents:
* Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
Aliquam hendrerit mi posuere lectus. Vestibulum enim wisi,
viverra nec, fringilla in, laoreet vitae, risus.
* Donec sit amet nisl. Aliquam semper ipsum sit amet velit.
Suspendisse id sem consectetuer libero luctus adipiscing.
If list items are separated by blank lines, Markdown will wrap the items in <p> tags in the HTML output.
List items may consist of multiple paragraphs. Each subsequent paragraph in a list item must be indented by either 4 spaces or one tab:
1. This is a list item with two paragraphs. Lorem ipsum dolor
sit amet, consectetuer adipiscing elit. Aliquam hendrerit
mi posuere lectus.
Vestibulum enim wisi, viverra nec, fringilla in, laoreet
vitae, risus. Donec sit amet nisl. Aliquam semper ipsum
sit amet velit.
2. Suspendisse id sem consectetuer libero luctus adipiscing.
To put a blockquote within a list item, the blockquote’s > delimiters need to be indented:
To put a code block within a list item, the code block needs to be indented twice — 8 spaces or two tabs:
It’s worth noting that it’s possible to trigger an ordered list by accident. To avoid this, you can backslash-escape the period:
Code Blocks⚓︎
Code Blocks
Pre-formatted code blocks are used for writing about programming or markup source code. Rather than forming normal paragraphs, the lines of a code block are interpreted literally. Markdown wraps a code block in both <pre> and <code> tags.
To produce a code block in Markdown, simply indent every line of the block by at least 4 spaces or 1 tab. For example, given this input:
Markdown will generate:
One level of indentation — 4 spaces or 1 tab — is removed from each line of the code block. For example, this:
will turn into:
<p>Here is an example of AppleScript:</p>
<pre><code>tell application "Foo"
beep
end tell
</code></pre>
A code block continues until it reaches a line that is not indented (or the end of the article).
Within a code block, ampersands (&) and angle brackets (< and >) are automatically converted into HTML entities. This makes it very easy to include example HTML source code using Markdown — just paste it and indent it, and Markdown will handle the hassle of encoding the ampersands and angle brackets. For example, this:
will turn into:
Regular Markdown syntax is not processed within code blocks. E.g., asterisks are just literal asterisks within a code block. This means it’s also easy to use Markdown to write about Markdown’s own syntax.
Horizontal Rules⚓︎
Horizontal Rules
You can produce a horizontal rule tag (<hr />) by placing three or more hyphens, asterisks, or underscores on a line by themselves. If you wish, you may use spaces between the hyphens or asterisks. Each of the following lines will produce a horizontal rule:
Span Elements⚓︎
Links⚓︎
Links
Markdown supports two style of links: inline and reference.
In both styles, the link text is delimited by [square brackets].
To create an inline link, use a set of regular parentheses immediately after the link text’s closing square bracket. Inside the parentheses, put the URL where you want the link to point, along with an optional title for the link, surrounded in quotes. For example:
This is [an example](http://example.com/ "Title") inline link.
[This link](http://example.net/) has no title attribute.
Will produce:
<p>This is <a href="http://example.com/" title="Title">
an example</a> inline link.</p>
<p><a href="http://example.net/">This link</a> has no
title attribute.</p>
If you’re referring to a local resource on the same server, you can use relative paths:
Reference-style links use a second set of square brackets, inside which you place a label of your choosing to identify the link:
You can optionally use a space to separate the sets of brackets:
Then, anywhere in the document, you define your link label like this, on a line by itself:
That is:
- Square brackets containing the link identifier (optionally indented from the left margin using up to three spaces);
- followed by a colon;
- followed by one or more spaces (or tabs);
- followed by the URL for the link;
- optionally followed by a title attribute for the link, enclosed in double or single quotes, or enclosed in parentheses.
The following three link definitions are equivalent:
[foo]: http://example.com/ "Optional Title Here"
[foo]: http://example.com/ 'Optional Title Here'
[foo]: http://example.com/ (Optional Title Here)
Note: There is a known bug in Markdown.pl 1.0.1 which prevents single quotes from being used to delimit link titles.
The link URL may, optionally, be surrounded by angle brackets:
You can put the title attribute on the next line and use extra spaces or tabs for padding, which tends to look better with longer URLs:
Link definitions are only used for creating links during Markdown processing, and are stripped from your document in the HTML output.
Link definition names may consist of letters, numbers, spaces, and punctuation — but they are not case sensitive. E.g. these two links:
are equivalent.
The implicit link name shortcut allows you to omit the name of the link, in which case the link text itself is used as the name. Just use an empty set of square brackets — e.g., to link the word “Google” to the google.com web site, you could simply write:
And then define the link:
Because link names may contain spaces, this shortcut even works for multiple words in the link text:
And then define the link:
Link definitions can be placed anywhere in your Markdown document. I tend to put them immediately after each paragraph in which they’re used, but if you want, you can put them all at the end of your document, sort of like footnotes.
Here’s an example of reference links in action:
I get 10 times more traffic from [Google] [1] than from
[Yahoo] [2] or [MSN] [3].
[1]: http://google.com/ "Google"
[2]: http://search.yahoo.com/ "Yahoo Search"
[3]: http://search.msn.com/ "MSN Search"
Using the implicit link name shortcut, you could instead write:
I get 10 times more traffic from [Google][] than from
[Yahoo][] or [MSN][].
[google]: http://google.com/ "Google"
[yahoo]: http://search.yahoo.com/ "Yahoo Search"
[msn]: http://search.msn.com/ "MSN Search"
Both of the above examples will produce the following HTML output:
<p>I get 10 times more traffic from <a href="http://google.com/"
title="Google">Google</a> than from
<a href="http://search.yahoo.com/" title="Yahoo Search">Yahoo</a>
or <a href="http://search.msn.com/" title="MSN Search">MSN</a>.</p>
For comparison, here is the same paragraph written using Markdown’s inline link style:
I get 10 times more traffic from [Google](http://google.com/ "Google")
than from [Yahoo](http://search.yahoo.com/ "Yahoo Search") or
[MSN](http://search.msn.com/ "MSN Search").
The point of reference-style links is not that they’re easier to write. The point is that with reference-style links, your document source is vastly more readable. Compare the above examples: using reference-style links, the paragraph itself is only 81 characters long; with inline-style links, it’s 176 characters; and as raw HTML, it’s 234 characters. In the raw HTML, there’s more markup than there is text.
With Markdown’s reference-style links, a source document much more closely resembles the final output, as rendered in a browser. By allowing you to move the markup-related metadata out of the paragraph, you can add links without interrupting the narrative flow of your prose.
Emphasis⚓︎
Emphasis
Markdown treats asterisks (*) and underscores (_) as indicators of emphasis. Text wrapped with one * or _ will be wrapped with an HTML <em> tag; double *’s or _’s will be wrapped with an HTML <strong> tag. E.g., this input:
will produce:
<em>single asterisks</em>
<em>single underscores</em>
<strong>double asterisks</strong>
<strong>double underscores</strong>
You can use whichever style you prefer; the lone restriction is that the same character must be used to open and close an emphasis span.
Emphasis can be used in the middle of a word:
But if you surround an * or _ with spaces, it’ll be treated as a literal asterisk or underscore.
To produce a literal asterisk or underscore at a position where it would otherwise be used as an emphasis delimiter, you can backslash escape it:
Images⚓︎
Images
Admittedly, it’s fairly difficult to devise a “natural” syntax for placing images into a plain text document format.
Markdown uses an image syntax that is intended to resemble the syntax for links, allowing for two styles: inline and reference.
Inline image syntax looks like this:
That is:
- An exclamation mark:
!; - followed by a set of square brackets, containing the
altattribute text for the image; - followed by a set of parentheses, containing the URL or path to the image, and an optional
titleattribute enclosed in double or single quotes.
Reference-style image syntax looks like this:
Where “id” is the name of a defined image reference. Image references are defined using syntax identical to link references:
As of this writing, Markdown has no syntax for specifying the dimensions of an image; if this is important to you, you can simply use regular HTML <img> tags.
Miscellaneous⚓︎
Automatic Links⚓︎
Automatic Links
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:
Markdown will turn this into:
Automatic links for email addresses work similarly, except that Markdown will also perform a bit of randomized decimal and hex entity-encoding to help obscure your address from address-harvesting spambots. For example, Markdown will turn this:
into something like this:
<a href="mailto:addre
ss@example.co
m">address@exa
mple.com</a>
which will render in a browser as a clickable link to “address@example.com”.
(This sort of entity-encoding trick will indeed fool many, if not most, address-harvesting bots, but it definitely won’t fool all of them. It’s better than nothing, but an address published in this way will probably eventually start receiving spam.)
Backslash Escapes⚓︎
Backslash Escapes
Markdown allows you to use backslash escapes to generate literal characters which would otherwise have special meaning in Markdown’s formatting syntax. For example, if you wanted to surround a word with literal asterisks (instead of an HTML <em> tag), you can use backslashes before the asterisks, like this:
Markdown provides backslash escapes for the following characters: