Lightweight markup language

A lightweight markup language (LML), also termed a simple or humane markup language, is a markup language with simple, unobtrusive syntax. It is designed to be easy to write using any generic text editor and easy to read in its raw form. Lightweight markup languages are used in applications where it may be necessary to read the raw document as well as the final rendered output.

For instance, a person downloading a software library might prefer to read the documentation in a text editor rather than a web browser. Another application for such languages is to provide for data entry in web-based publishing, such as weblogs and wikis, where the input interface is a simple text box. The server software then converts the input into a common document markup language like HTML.

History

Lightweight markup languages were originally used on text-only displays which could not display characters in italics or bold, so informal methods to convey this information had to be developed. This formatting choice was naturally carried forth to plain-text email communications. Console browsers may also resort to similar display conventions.

In 1986 international standard SGML provided facilities to define and parse lightweight markup languages using grammars and tag implication. The 1998 W3C XML is a profile of SGML that omits these facilities. However, no SGML document type definition (DTD) for any of the languages listed below is known.

Types

Lightweight markup languages can be categorized by their tag types. Like HTML (<b>bold</b>), some languages use named elements that share a common format for start and end tags (e.g. BBCode [b]bold[/b]), whereas proper lightweight markup languages are restricted to ASCII-only punctuation marks and other non-letter symbols for tags, but some also mix both styles (e.g. Textile bq. ) or allow embedded HTML (e.g. Markdown), possibly extended with custom elements (e.g. MediaWiki <ref>source</ref>).

Most languages distinguish between markup for lines or blocks and for shorter spans of texts, but some only support inline markup.

Some markup languages are tailored for a specific purpose, such as documenting computer code (e.g. POD, RD) or being converted to a certain output format (usually HTML) and nothing else, others are more general in application. This includes whether they are oriented on textual presentation or on data serialization.

Presentation oriented languages include AsciiDoc, atx, BBCode, Creole, Crossmark, Epytext, Haml, JsonML, MakeDoc, Markdown, Org-mode, POD, reST, RD, Setext, SiSU, SPIP, Xupl, Texy!, Textile, txt2tags, UDO and Wikitext.

Data serialization oriented languages include Curl (homoiconic, but also reads JSON; every object serializes), JSON, and YAML.

Comparison of language features

Comparing language features

Language	HTML export tool	HTML import tool	Tables	Link titles	class attribute	id attribute	Release date
AsciiDoc	Yes	Yes	Yes	Yes	Yes	Yes	2002-11-25[1]
BBCode	No	No	Yes	No	No	No	1998
Creole	No	No	Yes	No	No	No	2007-07-04[2]
GitHub Flavored Markdown	Yes	No	Yes	Yes	No	No	2011-04-28+
Jira Formatting Notation	Yes	No	Yes	Yes	No	No	2002+[3]
Markdown	Yes	Yes	No	Yes	Yes/No	Yes/No	2004-03-19[4][5]
Markdown Extra	Yes	Yes	Yes[6]	Yes	Yes	Yes	2013-04-11[7]
MediaWiki	Yes	Yes	Yes	Yes	Yes	Yes	2002[8]
MultiMarkdown	Yes	No	Yes	Yes	No	No	2009-07-13
Org-mode	Yes	Yes[9]	Yes	Yes	Yes	Yes	2003[10]
PmWiki	Yes[11]	Yes	Yes	Yes	Yes	Yes	2002-01
POD	Yes	?	No	Yes	?	?	1994
reStructuredText	Yes	Yes[9]	Yes	Yes	Yes	auto	2002-04-02[12]
Slack	No	No	No	Yes	No	No	2013+[13][14]
TiddlyWiki	Yes	No	Yes	Yes	Yes	No	2004-09[15]
Textile	Yes	No	Yes	Yes	Yes	Yes	2002-12-26[16]
Texy	Yes	Yes	Yes	Yes	Yes	Yes	2004[17]
txt2tags	Yes	Yes[18]	Yes[19]	Yes	Yes/No	Yes/No	2001-07-26[20]
WhatsApp	No	No	No	No	No	No	2016-03-16[21]

Markdown's own syntax does not support class attributes or id attributes; however, since Markdown supports the inclusion of native HTML code, these features can be implemented using direct HTML. (Some extensions may support these features.)

txt2tags' own syntax does not support class attributes or id attributes; however, since txt2tags supports inclusion of native HTML code in tagged areas, these features can be implemented using direct HTML when saving to an HTML target.[22]

Comparison of implementation features

Comparing implementations, especially output formats

Language	Implementations	XHTML	Con/LaTeX	PDF	DocBook	ODF	EPUB	DOC(X)	LMLs	Other	License
AsciiDoc	Python, Ruby, JavaScript, Java	XHTML	LaTeX	PDF	DocBook	ODF	EPUB	No	—	Man page etc.	GNU GPL, MIT
BBCode	Perl, PHP, C#, Python, Ruby	(X)HTML	No	No	No	No	No	No	—	—	Public Domain
Creole	PHP, Python, Ruby, JavaScript[23]	Depends on implementation									CC_BY-SA 1.0
GitHub Flavored Markdown	Haskell (Pandoc)	HTML	LaTeX, ConTeXt	PDF	DocBook	ODF	EPUB	DOC	AsciiDoc, reST	OPML	GPL
	Java,[24] JavaScript,[25][26][27] PHP,[28][29] Python,[30] Ruby[31]	HTML[25][26][27][29][30]	No	No	No	No	No	No	—	—	Proprietary
Markdown	Perl (originally), C,[32][33] Python,[34] JavaScript, Haskell,[9] Ruby,[35] C#, Java, PHP	HTML	LaTeX, ConTeXt	PDF	DocBook	ODF	EPUB	RTF	MediaWiki, reST	Man page, S5 etc.	BSD-style & GPL (both)
Markdown Extra	PHP (originally), Python, Ruby	XHTML	No	No	No	No	No	No	—	—	BSD-style & GPL (both)
MediaWiki	Perl, PHP, Haskell, Python	XHTML	No	No	No	No	No	No	—	—	GNU GPL
MultiMarkdown	C, Perl	(X)HTML	LaTeX	PDF	No	ODF	No	DOC, RTF	—	OPML	GPL, MIT
Org-mode	Emacs Lisp, Ruby (parser only), Perl, OCaml	XHTML	LaTeX	PDF	DocBook	ODF	EPUB[36]	DOCX[36]	Markdown	TXT, XOXO, iCalendar, Texinfo, man, contrib: groff, s5, deck.js, Confluence Wiki Markup,[37] TaskJuggler, RSS, FreeMind	GPL
PmWiki	PHP	XHTML 1.0 Transitional, HTML5	No	PDF export addons	No	No	EPUB export addon	No	—	—	GNU GPL
POD	Perl	(X)HTML, XML	LaTeX	PDF	DocBook	No	No	RTF	—	Man page, plain text	Artistic License, Perl's license
reStructuredText	Python,[38][39] Haskell (Pandoc), Java,	HTML, XML	LaTeX	PDF	DocBook	ODF	EPUB	DOC	—	man, S5, Devhelp, QT Help, CHM, JSON	Public Domain
Textile	PHP, JavaScript, Java, Perl, Python, Ruby, ASP, C#, Haskell	XHTML	No	No	No	No	No	No	—	—	Textile License
Texy!	PHP, C#	(X)HTML	No	No	No	No	No	No	—	—	GNU GPL v2 License
txt2tags	Python,[40] PHP[41]	(X)HTML, SGML	LaTeX	PDF	DocBook	ODF	EPUB	DOC	Creole, AsciiDoc, MediaWiki, MoinMoin, PmWiki, DokuWiki, Google Code Wiki	roff, man, MagicPoint, Lout, PageMaker, ASCII Art, TXT	GPL

Comparison of lightweight markup language syntax

Inline span syntax

Although usually documented as yielding italic and bold text, most lightweight markup processors output semantic HTML elements em and strong instead. Monospaced text may either result in semantic code or presentational tt elements. Few languages make a distinction, e.g. Textile, or allow the user to configure the output easily, e.g. Texy.

LMLs sometimes differ for multi-word markup where some require the markup characters to replace the inter-word spaces (infix). Some languages require a single character as prefix and suffix, other need doubled or even tripled ones or support both with slightly different meaning, e.g. different levels of emphasis.

Comparison of text formatting syntax

HTML output	<strong>strongly emphasized</strong>	<em>emphasized text</em>	<code>code</code>	semantic
	<b>bold text</b>	<i>italic text</i>	<tt>monospace text</tt>	presentational
AsciiDoc	*bold text*	'italic text'	+monospace text+	Can double operators to apply formatting where there is no word boundary (for example **b**old t**ex**t yields bold text).
		_italic text_	`monospace text`
ATX	*bold text*	_italic text_	monospace text|	email style
BBCode	[b]bold text[/b]	[i]italic text[/i]	[code]monospace text[/code]	Formatting works across line breaks.
Creole	**bold text**	//italic text//	{{{monospace text}}}	Triple curly braces are for nowiki which is optionally monospace.
Jira Formatting Notation	*bold text*	_italic text_	{{monospace text}}
Markdown[42]	**bold text**	*italic text*	`monospace text`	semantic HTML tags
	__bold text__	_italic text_
MediaWiki	'''bold text'''	''italic text''	<code>monospace text</code>	mostly resorts to inline HTML
Org-mode	*bold text*	/italic text/	=code=
			~verbatim~
PmWiki	'''bold text'''	''italic text''	@@monospace text@@
reST	**bold text**	*italic text*	``monospace text``
Setext	**bold text**	~italic text~	N/A
Textile[43]	*strong*	_emphasis_	@monospace text@	semantic HTML tags
	**bold text**	__italic text__		presentational HTML tags
Texy!	**bold text**	*italic text*	`monospace text`	semantic HTML tags by default, optional support for presentational tags
		//italic text//
TiddlyWiki	''bold text''	//italic text//	`monospace text`
			``monospace text``
txt2tags	**bold text**	//italic text//	``monospace text``
POD	B<bold text>	I<italic text>	C<monospace text>	Indented text is also shown as monospaced code.
Slack	*bold text*	_italic text_	`monospace text`	```block of monospaced text```
WhatsApp	*bold text*	_italic text_	```monospace text```

Emphasis syntax

In HTML, text is emphasized with the <em> and <strong> element types, whereas <i> and <b> traditionally mark up text to be italicized or bold-faced, respectively.

Microsoft Word and Outlook, and accordingly other word processors and mail clients that strive for a similar user experience, support the basic convention of using asterisks for boldface and underscores for italic style. While Word removes the characters, Outlook retains them.

Italic type or normal emphasis

Code	AsciiDoc	ATX	Creole	Jira	Markdown	MediaWiki	Org-mode	PmWiki	reST	Setext	Slack	Textile	Texy!	TiddlyWiki	txt2tags	WhatsApp
*italic*	No	No	No	No	Yes	No	No	No	Yes	No	No	No	Yes	No	No	No
**italic**	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No
_italic_	Yes	Yes	No	Yes	Yes	No	No	No	No	No	Yes	Yes	No	No	No	Yes
__italic__	Yes	No	No	No	No	No	No	No	No	No	No	Yes	No	No	No	No
'italic'	Yes	No	No	No	No	No	No	No	No	No	No	No	No	No	No	No
''italic''	Yes	No	No	No	No	Yes	No	Yes	No	No	No	No	No	No	No	No
/italic/	No	No	No	No	No	No	Yes	No	No	No	No	No	No	No	No	No
//italic//	No	No	Yes	No	No	No	No	No	No	No	No	No	Yes	Yes	Yes	No
~italic~	No	No	No	No	No	No	No	No	No	Yes	No	No	No	No	No	No

Bold face or strong emphasis

Code	AsciiDoc	ATX	Creole	Jira	Markdown	MediaWiki	Org-mode	PmWiki	reST	Setext	Slack	Textile	Texy!	TiddlyWiki	txt2tags	WhatsApp
*bold*	Yes	Yes	No	Yes	No	No	Yes	No	No	No	Yes	Yes	No	No	No	Yes
**bold**	Yes	No	Yes	No	Yes	No	No	No	Yes	Yes	No	Yes	Yes	No	Yes	No
__bold__	No	No	No	No	Yes	No	No	No	No	No	No	No	No	No	No	No
''bold''	No	No	No	No	No	No	No	No	No	No	No	No	No	Yes	No	No
'''bold'''	No	No	No	No	No	Yes	No	Yes	No	No	No	No	No	No	No	No

Editorial syntax

In HTML, removed or deleted and inserted text is marked up with the <del> and <ins> element types, respectively. However, legacy element types <s> or <strike> and <u> are still also available for stricken and underlined spans of text.

Underlined or inserted text

Code	Jira	Markdown	Org-mode	Setext	TiddlyWiki	txt2tags
_underline_	No	Optional	Yes	Yes	No	No
__underline__	No	Optional	No	No	Yes	Yes
+underline+	Yes	No	No	No	No	No

AsciiDoc, ATX, Creole, MediaWiki, PmWiki, reST, Slack, Textile, Texy! and WhatsApp do not support dedicated markup for underlining text.

Strike-through or deleted text

Code	Jira	Markdown	Org-mode	Slack	TiddlyWiki	txt2tags	WhatsApp
~stricken~	No	No	No	Yes	No	No	Yes
~~stricken~~	No	GFM	No	No	Yes	No	No
+stricken+	No	No	Yes	No	No	No	No
-stricken-	Yes	No	No	No	No	No	No
--stricken--	No	No	No	No	No	Yes	No

AsciiDoc, ATX, Creole, MediaWiki, PmWiki, reST, Setext, Textile and Texy! do not support dedicated markup for striking through text.

Programming syntax

Quoted computer code is traditionally presented in typewriter-like fonts where each character occupies the same fixed width. HTML offers the semantic <code> and the deprecated, presentational <tt> element types for this task.

Monospaced font, teletype text or code

Code	AsciiDoc	ATX	Creole	Jira	Markdown	Org-mode	PmWiki	reST	Slack	Textile	Texy!	TiddlyWiki	txt2tags	WhatsApp
@code@	No	No	No	No	No	No	No	No	No	Yes	No	No	No	No
@@code@@	No	No	No	No	No	No	Yes	No	No	No	No	No	No	No
`code`	Yes	No	No	No	Yes	No	No	No	Yes	No	Yes	Yes	No	No
``code``	Yes	No	No	No	Yes	No	No	Yes	No	No	No	Yes	Yes	No
```code```	No	No	No	No	Yes	No	No	No	Yes/No	No	No	Yes	No	Yes
=code=	No	No	No	No	No	Yes	No	No	No	No	No	No	No	No
~code~	No	No	No	No	No	Yes	No	No	No	No	No	No	No	No
+code+	Yes	No	No	No	No	No	No	No	No	No	No	No	No	No
++code++	Yes	No	No	No	No	No	No	No	No	No	No	No	No	No
{{code}}	No	No	No	Yes	No	No	No	No	No	No	No	No	No	No
{{{code}}}	No	No	Yes	No	No	No	No	No	No	No	No	No	No	No
code|	No	Yes	No	No	No	No	No	No	No	No	No	No	No	No

Mediawiki and Setext do not provide lightweight markup for inline code spans.

Heading syntax

Headings are usually available in up to six levels, but the top one is often reserved to contain the same as the document title, which may be set externally. Some documentation may associate levels with divisional types, e.g. part, chapter, section, article or paragraph.

Most LMLs follow one of two styles for headings, either Setext-like underlines or atx-like[44] line markers, or they support both.

Underlined headings

Level 1 Heading
===============

Level 2 Heading
---------------

Level 3 Heading
~~~~~~~~~~~~~~~

The first style uses underlines, i.e. repeated characters (e.g. equals =, hyphen - or tilde ~, usually at least two or four times) in the line below the heading text.

Underlined heading levels

Chars:	=	-	~	*	#	+	^	_	:	"	'	`	.	min
Markdown	1	2	No	No	No	No	No	No	No	No	No	No	No	1
Setext	1	2	No	No	No	No	No	No	No	No	No	No	No	?
AsciiDoc	1	2	3	No	No	No	No	No	No	No	No	No	No	2
Texy!	3	4	No	2	1	No	No	No	No	No	No	No	No	3
reStructuredText	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	heading width

RST determines heading levels dynamically, which makes authoring more individual on the one hand, but complicates merges from external sources on the other hand.

Prefixed headings

# Level 1 Heading
## Level 2 Heading ##
### Level 3 Heading ###

The second style is based on repeated markers (e.g. hash #, equals = or asterisk *) at the start of the heading itself, where the number of repetitions indicates the (sometimes inverse) heading level. Most languages also support the reduplication of the markers at the end of the line, but whereas some make them mandatory, others do not even expect their numbers to match.

Line prefix (and suffix) headings

Character:	=	#	*	!	+	Suffix	Levels	Indentation
AsciiDoc	Yes	No	No	No	No	Optional	1–6	No
ATX	No	Yes	No	No	No	No	unlimited	?
Creole	Yes	No	No	No	No	Optional	1–6	No
MediaWiki	Yes	No	No	No	No	Yes	1–6	No
TiddlyWiki	No	No	No	Yes	No	No	1–6	No
txt2tags	Yes	No	No	No	Yes	Yes	1–6	No
Markdown	No	Yes	No	No	No	Optional	1–6	No
Texy!	Yes	Yes	No	No	No	Optional	6–1 or 1–6, dynamic	No
Org-mode	No	No	Yes	No	No	No	1– +∞	alternative[45][46][47]
PmWiki	No	No	No	Yes	No	Optional	1–6	No

Org-mode supports indentation as a means of indicating the level.

BBCode does not support section headings at all.

POD and Textile choose the HTML convention of numbered heading levels instead.

Other heading formats

Language	Format
POD	=head1 Level 1 Heading =head2 Level 2 Heading
Textile,[43] Jira[3]	h1. Level 1 Heading h2. Level 2 Heading h3. Level 3 Heading h4. Level 4 Heading h5. Level 5 Heading h6. Level 6 Heading

Microsoft Word supports auto-formatting paragraphs as headings if they do not contain more than a handful of words, no period at the end and the user hits the enter key twice. For lower levels, the user may press the tabulator key the according number of times before entering the text, i.e. one through eight tabs for heading levels two through nine.

Link syntax

Hyperlinks can either be added inline, which may clutter the code because of long URLs, or with named alias or numbered id references to lines containing nothing but the address and related attributes and often may be located anywhere in the document. Most languages allow the author to specify text Text to be displayed instead of the plain address http://example.com and some also provide methods to set a different link title Title which may contain more information about the destination.

LMLs that are tailored for special setups, e.g. wikis or code documentation, may automatically generate named anchors (for headings, functions etc.) inside the document, link to related pages (possibly in a different namespace) or provide a textual search for linked keywords.

Most languages employ (double) square or angular brackets to surround links, but hardly any two languages are completely compatible. Many can automatically recognize and parse absolute URLs inside the text without further markup.

Inline hyperlink syntax

Languages	Basic syntax	Text syntax	Title syntax
BBCode, Creole, MediaWiki, PmWiki	http://example.com
Textile		"Text":http://example.com	"Text (Title)":http://example.com
Texy!			"Text .(Title)":http://example.com
AsciiDoc		http://example.com[Text]
Slack		Text>
TiddlyWiki		[[Text|http://example.com]]
Jira	[http://example.com]	http://example.com]
txt2tags		[Text http://example.com]
MediaWiki		[http://example.com Text]
Creole, MediaWiki, PmWiki	[[Name]]	[[Name|Text]]
Org-mode		[[Name][Text]]
TiddlyWiki		[[Text|Name]]
Creole	[[Namespace:Name]]	[[Namespace:Name|Text]]
Org-mode		[[Namespace:Name][Text]]
Creole, PmWiki	[[http://example.com]]	[[http://example.com|Text]]
BBCode		[url]http://example.com[/url]	[url=http://example.com]Text[/url]
Markdown	<http://example.com>	[Text](http://example.com)	[Text](http://example.com "Title")
reStructuredText		`Text <http://example.com/>`_
POD	L</Name>
POD	L<http://example.com/>

Reference syntax

Languages	Text syntax	Title syntax
reStructuredText	… Name_ … .. _Name: http://example.com
ATX	… [Text] … [Text] http://example.com
AsciiDoc	… [[id]] … <<id>>	… [[id]] … <<id,Text>>
	… anchor:id … xref:id	… anchor:id … xref:id[Text]
Markdown	… [Text][id] … [id]: http://example.com	… [Text][id] … [id]: http://example.com "Title"
	… [Text][] … [Text]: http://example.com	… [Text][] … [Text]: http://example.com "Title"
	… [Text] … [Text]: http://example.com	… [Text] … [Text]: http://example.com "Title"
Textile	… "Text":alias … [alias]http://example.com	… "Text":alias … [alias (Title)]http://example.com
Texy!	… "Text":alias … [alias]: http://example.com	… "Text":alias … [alias]: http://example.com .(Title)

Org-mode's normal link syntax does a text search of the file. You can also put in dedicated targets with <<id>>.

List syntax

HTML requires an explicit element for the list, specifying its type, and one for each list item, but most lightweight markup languages need only different line prefixes for the bullet points or enumerated items. Some languages rely on indentation for nested lists, others use repeated parent list markers.

Unordered, bullet list items

Characters:	*	-	+	#	.	·	•	_	:	–	—	indent	skip	nest
Markdown	Yes	Yes	Yes	No	No	No	No	No	No	No	No	0–3	1–3	indent
MediaWiki, TiddlyWiki	Yes	No	No	No	No	No	No	No	No	No	No	0	1+	repeat
Org-mode	Yes[48]	Yes	Yes	No	No	No	No	No	No	No	No	0+		indent
Jira	Yes	Yes	No	No	No	No	No	No	No	No	No	0	1+	repeat

Microsoft Word automatically converts paragraphs that start with an asterisk *, hyphen-minus - or greater-than bracket > followed by a space or horizontal tabulator as bullet list items. It will also start an enumerated list for the digit 1 and the case-insensitive letters a (for alphabetic lists) or i (for roman numerals), if they are followed by a period ., a closing round parenthesis ), a greater-than sign > or a hyphen-minus - and a space or tab; in case of the round parenthesis an optional opening one ( before the list marker is also supported.

Languages differ on whether they support optional or mandatory digits in numbered list items, which kinds of enumerators they understand (e.g. decimal digit 1, roman numerals i or I, alphabetic letters a or A) and whether they support to keep explicit values in the output format. Some Markdown dialects, for instance, will respect a start value other than 1, but ignore any other explicit value.

Ordered, enumerated list items

Chars:	#	#1	1.	1)	1]	1}	(1)	[1]	{1}	a.	A.	i.	I.	indent	skip	nest
Markdown	No	No	Yes	Yes	No	No	No	No	No	No	No	No	No	0–3	1–3	indent
MediaWiki, TiddlyWiki	Yes	No	No	No	No	No	No	No	No	No	No	No	No	0	1+	repeat
Org-mode	No	No	Yes	Yes	No	No	No	No	No	Optional		No	No	0+		indent
Jira	Yes	No	No	No	No	No	No	No	No	No	No	No	No	0	1+	repeat

Slack assists the user in entering enumerated and bullet lists, but does not actually format them as such, i.e. it just includes a leading digit followed by a period and a space or a bullet character • in front of a line.

Labeled, glossary, definition list syntax

Languages	Term being defined	Definition of the term
MediaWiki	; Term	: Definition
TiddlyWiki
Org-mode	- Term :: Definition

See also

• Lightweight programming language
• Comparison of document-markup languages
• Comparison of documentation generators
• WikiText
• Markdown

References

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24. pegdown: A Java library for Markdown processing
25. gfms: Github Flavored Markdown Server
26. marked: A full-featured markdown parser and compiler, written in JavaScript. Built for speed.
27. node-gfm: GitHub flavored markdown to HTML converter
28. Parsedown: Markdown parser written in PHP
29. Ciconia: Markdown parser written in PHP
30. Grip: GitHub Readme Instant Preview
31. github-markdown: Self-contained Markdown parser for GitHub
32. peg-markdown is an implementation of markdown in C.
33. Discount is also an implementation of markdown in C.
34. "Python-Markdown". Github.com. Retrieved 2013-10-08.
35. Bruce Williams <http://codefluency.com>, for Ruby Central <http://rubycentral.org>. "kramdown: Project Info". RubyForge. Archived from the original on 2013-08-07. Retrieved 2013-10-08.
36. "Via ox-pandoc and pandoc itself".
37. Atlassian. "Confluence 4.0 Editor - What's Changed for Wiki Markup Users (Confluence Wiki Markup is dead)". Retrieved 2018-03-28.
38. Docutils is an implementation of ReStructuredText in Python
39. Sphinx is an implementation of ReStructuredText in Python and Docutils with a number of output format Builders
40. Aurelio Jargas www.aurelio.net (2012-01-11). "txt2tags". txt2tags. Retrieved 2013-10-08.
41. "txt2tags.class.php - online convertor [sic]". Txt2tags.org. Retrieved 2013-10-08.
42. "Markdown Syntax". Daringfireball.net. Retrieved 2013-10-08.
43. Textile Syntax Archived 2010-08-12 at the Wayback Machine
44. "atx, the true structured text format" by Aaron Swartz (2002)
45. "The Org Manual: section "A Cleaner Outline View"". Retrieved 14 June 2020.
46. "using org-adapt-indentation".
47. "using org-indent-mode or org-indent".
48. Footnote in official manual "When using ‘*’ as a bullet, lines must be indented so that they are not interpreted as headlines. Also, when you are hiding leading stars to get a clean outline view, plain list items starting with a star may be hard to distinguish from true headlines. In short: even though ‘*’ is supported, it may be better to not use it for plain list items."

External links

• C2's list
• Curl Markup to replace HTML+CSS+JS
• Inhabitants of the authoring ecosphere
• List at otl website
• Humane Text Formats - A comparison (obsolete)
• Pandoc: a versatile inter-format converter