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.

Gemtext does not have any inline formatting, monospaced text (called preformatted text in the context of Gemtext) must have the opening and closing ``` on their own lines.

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^[47] line markers, or they support both.

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

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

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

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

=head1 Level 1 Heading
=head2 Level 2 Heading

h1. Level 1 Heading
h2. Level 2 Heading
h3. Level 3 Heading
h4. Level 4 Heading
h5. Level 5 Heading
h6. Level 6 Heading

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.

Gemtext and setext links must be on a line by themselves, they cannot be used inline.

… [[id]] …
<<id>>

… [[id]] …
<<id,Text>>

… anchor:id …
xref:id

… anchor:id …
xref:id[Text]

… [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"

… Name_ …
.. _Name: http://example.com

… Link_name_ …
^.. _Link_name URL

… "Text":alias …
[alias]http://example.com

… "Text":alias …
[alias (Title)]http://example.com

… "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.

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.

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.