For more information, please see Wiki Page Editor and Wiki Syntax

Wiki Syntax
Bold text     __text__
Italic text     2 single quotes (').     '"text"'
Underlined text     ===text===
Colored text ~~#FFEE33:text~~ or ~~yellow:text~~. Will display using the indicated HTML color or color name. Color name can contain two colors separated by a comma. In this case, the first color would be the foreground and the second one the background.
Deleted text     2 dashes "-".     --text--
Headings !heading1, !!heading2, !!!heading3
Show/Hide !+, !!- show/hide heading section. + (shown) or - (hidden) by default.
Autonumbered Headings !#, !!#, !+#, !-# ...
Table of contents {toc}, {maketoc} prints out a table of contents for the current page based on structures (toc) or ! headings (maketoc). Common optional parameters for maketoc are: title|maxdepth|levels|nums, and for toc are: order|showdesc|shownum|structId|maxdepth|pagename.
Horizontal rule     ----
Text box     ^Box content^
Centered text     ::text::
Dynamic variables %Name% Inserts an editable variable
External links use square brackets for an external link: [URL], [URL|link_description],[URL|link_description|relation] or [URL|description|relation|nocache] (that last prevents the local Wiki from caching the linked page; relation can be used to insert rel attribute for the link - useful e.g. for shadowbox). For an external Wiki, use ExternalWikiName:PageName or ((External Wiki Name: Page Name))
Square Brackets Use [[foo] to show [foo].
Wiki References ((page)) or ((page|description)) for wiki references
Lists * for bullet lists, # for numbered lists, ;Word:definition for definiton lists
Indentation +, ++ Creates an indentation for each plus (useful in list to continue at the same level)
Tables || row1-col1 | row1-col2 | row1-col3 row2-col1 | row2-col2 | row2-col3 ||
Title bar     -=Title=-
Monospace font     -+Code sample+-
Line break %%% (very useful especially in tables)
Multi-page pages Use ...page... to separate pages
Non parsed sections ~np~ data ~/np~ Prevents wiki parsing of the enclosed data.
Preformated sections ~pp~ data ~/pp~ Displays preformated text/code; no Wiki processing is done inside these sections (as with np), and the spacing is fixed (no word wrapping is done). ~pre~ data ~/pre~ also displayes preformatted text with fixed spacing, but wiki processing still occurs on the text.
Comments ~tc~ Tiki Comment ~/tc~ makes a Tiki comment. It will be completely removed from the display, but saved in the file for future reference. ~hc~ HTML Comment ~/hc~ makes an HTML comment. It will be inserted as a comment in the output HTML; these are not normally displayed in browsers, but can be seen using "View Source" or similar.
Direction {r2l}, {l2r}, {rm}, {lm}Insert resp. right-to-left and left-to-right text direction DIV (up to end of text) and markers for langages as arabic or hebrew.
Special characters ~hs~ hard space, ~c~ ©, ~amp~ &, ~lt~ <, ~gt~ >, ~ldq~ “, ~rdq~ ”, ~lsq~ ‘, ~rsq~ ’, ~--~ —, ~bs~ \, numeric between ~ for HTML numeric characters entity

Because the Wiki paragraph formatting feature is on, all groups of non-blank lines are collected into paragraphs. Lines can be of any length, and will be wrapped together with the next line. Paragraphs are separated by blank lines.

Note that plugin arguments can be enclosed with double quotes ("); this allows them to contain , or = or >.
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Description
Author author View author contributions to a wiki page
Box box Creates a formatted box with a title bar
Center center Center text
Code code Display code syntax with line numbers and color highlights
Comment comment Display a comment area for any specified object
Div div Define and format sections of a page or text
Definition List dl Create a definition list
Fade fade Create a link that shows/hides initially hidden content
Fancy List fancylist Create a fancy-looking list
Fancy Table fancytable Create a formatted table
File file Link to a file that's attached or in a file gallery or archive. See PluginFiles for more functionality.
Files files List files by ID, gallery or category, or show a slideshow of image files
Flash Video flash Embed a video or audio file
Google Map googlemap Display a Google map
Group group Display content based on the user's groups or friends
Group List grouplist List all groups or just groups that include a certain group
Group Stats groupstat Show the distribution of users among groups
HTML html Add HTML to a page
Image img Display custom formatted images
Include include Include content from a wiki page
Invite invite Invite a user to join your groups
Table of Contents (Page) maketoc Add a table of contents to a page
Map map Display a map
Media Player mediaplayer Add a media player to a page
Mouseover mouseover Display hidden content by mousing over a text
Now now Display the current date or time
HTML (Object Oriented) version, for proof of concept oohtml Add HTML to a page
Quote quote Format text as a quote
Remarks Box remarksbox Displays a comment, tip, note or warning box
RSS Feed rss Display items from an RSS feed
Sort sort Sort lines of text
Split split Easily arrange content on a page into rows and columns
Subscript sub Apply subscript font to text
Superscript sup Apply superscript font to text
Tabs tabs Arrange content in tabs
Transclude transclude Include the content of another page with certain changes
Twitter twitter Display the activity for a twitter account
User Link userlink Display a link to a user's information page
Vimeo vimeo Display a Vimeo video
YouTube youtube Display a YouTube video