Note: This document is itself written using Markdown; you +can see the source for it by adding '.text' to the URL.
+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.
+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.
+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:
http://images.google.com/images?num=30&q=larry+bird
+you need to encode the URL as:
+http://images.google.com/images?num=30&q=larry+bird
+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:
+AT&T
+Markdown will translate it to:
+AT&T
+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:
+4 < 5
+Markdown will translate it to:
+4 < 5
+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.)
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.
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:
+This is an H1
+=============
+
+This is an H2
+-------------
+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:
+# This is an H1
+
+## This is an H2
+
+###### This is an H6
+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.) :
+# This is an H1 #
+
+## This is an H2 ##
+
+### This is an H3 ######
+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 >:
> This is the first level of quoting.
+>
+> > This is nested blockquote.
+>
+> Back to the first level.
+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.
+Markdown supports ordered (numbered) and unordered (bulleted) lists.
+Unordered lists use asterisks, pluses, and hyphens -- interchangably +-- as list markers:
+* Red
+* Green
+* Blue
+is equivalent to:
++ Red
++ Green
++ Blue
+and:
+- Red
+- Green
+- Blue
+Ordered lists use numbers followed by periods:
+1. Bird
+2. McHale
+3. Parish
+It's important to note that the actual numbers you use to mark the +list have no effect on the HTML output Markdown produces. The HTML +Markdown produces from the above list is:
+<ol>
+<li>Bird</li>
+<li>McHale</li>
+<li>Parish</li>
+</ol>
+If you instead wrote the list in Markdown like this:
+1. Bird
+1. McHale
+1. Parish
+or even:
+3. Bird
+1. McHale
+8. Parish
+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.
+If you do use lazy list numbering, however, you should still start the +list with the number 1. At some point in the future, Markdown may support +starting ordered lists at an arbitrary number.
+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.
+But if you want to be lazy, you don't have to:
+* 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. For example, this input:
* Bird
+* Magic
+will turn into:
+<ul>
+<li>Bird</li>
+<li>Magic</li>
+</ul>
+But this:
+* Bird
+
+* Magic
+will turn into:
+<ul>
+<li><p>Bird</p></li>
+<li><p>Magic</p></li>
+</ul>
+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.
+It looks nice if you indent every line of the subsequent +paragraphs, but here again, Markdown will allow you to be +lazy:
+* This is a list item with two paragraphs.
+
+ This is the second paragraph in the list item. You're
+only required to indent the first line. Lorem ipsum dolor
+sit amet, consectetuer adipiscing elit.
+
+* Another item in the same list.
+To put a blockquote within a list item, the blockquote's >
+delimiters need to be indented:
* A list item with a blockquote:
+
+ > This is a blockquote
+ > inside a list item.
+To put a code block within a list item, the code block needs +to be indented twice -- 8 spaces or two tabs:
+* A list item with a code block:
+
+ <code goes here>
+It's worth noting that it's possible to trigger an ordered list by +accident, by writing something like this:
+1986. What a great season.
+In other words, a number-period-space sequence at the beginning of a +line. To avoid this, you can backslash-escape the period:
+1986\. What a great season.
+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:
+This is a normal paragraph:
+
+ This is a code block.
+Markdown will generate:
+<p>This is a normal paragraph:</p>
+
+<pre><code>This is a code block.
+</code></pre>
+One level of indentation -- 4 spaces or 1 tab -- is removed from each +line of the code block. For example, this:
+Here is an example of AppleScript:
+
+ tell application "Foo"
+ beep
+ end tell
+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:
<div class="footer">
+ © 2004 Foo Corporation
+ </div>
+will turn into:
+<pre><code><div class="footer">
+ &copy; 2004 Foo Corporation
+</div>
+</code></pre>
+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.
+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:
* * *
+
+***
+
+*****
+
+- - -
+
+---------------------------------------
+
+_ _ _
+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:
+See my [About](/about/) page for details.
+Reference-style links use a second set of square brackets, inside +which you place a label of your choosing to identify the link:
+This is [an example][id] reference-style link.
+You can optionally use a space to separate the sets of brackets:
+This is [an example] [id] reference-style link.
+Then, anywhere in the document, you define your link label like this, +on a line by itself:
+[id]: http://example.com/ "Optional Title Here"
+That is:
+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:
+[id]: <http://example.com/> "Optional Title Here"
+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:
+[id]: http://example.com/longish/path/to/resource/here
+ "Optional Title Here"
+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:
+[link text][a]
+[link text][A]
+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:
+[Google][]
+And then define the link:
+[Google]: http://google.com/
+Because link names may contain spaces, this shortcut even works for +multiple words in the link text:
+Visit [Daring Fireball][] for more information.
+And then define the link:
+[Daring Fireball]: http://daringfireball.net/
+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.
+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:
*single asterisks*
+
+_single underscores_
+
+**double asterisks**
+
+__double underscores__
+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:
+un*frigging*believable
+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:
+\*this text is surrounded by literal asterisks\*
+To indicate a span of code, wrap it with backtick quotes (`).
+Unlike a pre-formatted code block, a code span indicates code within a
+normal paragraph. For example:
Use the `printf()` function.
+will produce:
+<p>Use the <code>printf()</code> function.</p>
+To include a literal backtick character within a code span, you can use +multiple backticks as the opening and closing delimiters:
+``There is a literal backtick (`) here.``
+which will produce this:
+<p><code>There is a literal backtick (`) here.</code></p>
+The backtick delimiters surrounding a code span may include spaces -- +one after the opening, one before the closing. This allows you to place +literal backtick characters at the beginning or end of a code span:
+A single backtick in a code span: `` ` ``
+
+A backtick-delimited string in a code span: `` `foo` ``
+will produce:
+<p>A single backtick in a code span: <code>`</code></p>
+
+<p>A backtick-delimited string in a code span: <code>`foo`</code></p>
+With a code span, ampersands and angle brackets are encoded as HTML +entities automatically, which makes it easy to include example HTML +tags. Markdown will turn this:
+Please don't use any `<blink>` tags.
+into:
+<p>Please don't use any <code><blink></code> tags.</p>
+You can write this:
+`—` is the decimal-encoded equivalent of `—`.
+to produce:
+<p><code>&#8212;</code> is the decimal-encoded
+equivalent of <code>&mdash;</code>.</p>
+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:
+!;alt
+attribute text for the image;title attribute enclosed in double
+or single quotes.Reference-style image syntax looks like this:
+![Alt text][id]
+Where "id" is the name of a defined image reference. Image references +are defined using syntax identical to link references:
+[id]: url/to/image "Optional title attribute"
+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.
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:
+<http://example.com/>
+Markdown will turn this into:
+<a href="http://example.com/">http://example.com/</a>
+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:
+<address@example.com>
+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.)
+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:
\*literal asterisks\*
+Markdown provides backslash escapes for the following characters:
+\ backslash
+` backtick
+* asterisk
+_ underscore
+{} curly braces
+[] square brackets
+() parentheses
+# hash mark
++ plus sign
+- minus sign (hyphen)
+. dot
+! exclamation mark
+