Edit: sandbox

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

Also available here: Plugins help

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)
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 off, each line will be presented as you write it. This means that if you want paragraphs to be wrapped properly, a paragraph should be all together on one line.

Note that plugin arguments can be enclosed with double quotes ("); this allows them to contain , or = or >.
More help here

Description
Attachment Displays an attachment or a list of them
Box Insert theme-styled box on wiki page
Category Insert list of items with the current/given category in the wiki page
Category Orphans Display Tiki objects that have not been categorized
Category Path Insert the full category path for each category that this wiki page belongs to
Center Centers the plugin content in the wiki page
Code Displays a snippet of code
Div Insert a division block, span, blockquote or other text formatting on wiki page.
Definition List Creates a definition list
Fade Displays a label. On click, the block of content will fade in and fade out.
Fancy List Creates a fancy-looking list
Fancy Table Displays the data using the Tikiwiki odd/even table style
File Displays a link to an attachment to a wiki page and can display an image attachment.
Files Displays a list of files from the File Gallery
Flash video Displays a Flash (.swf) file in the wiki page
Group Display wiki text if user is in one of listed groups
Group Stats Displays some stat about group belonging
Image Display images
Include Include a page's content.
Invite Invite an email in groups.
Kaltura video Displays a KALTURA video on the wiki page
Mediaplayer Simple mp3 or flv Player
Insert Module Displays a module inline in a wiki page. More parameters can be added, not supported by UI.
Mouseover Create a mouseover feature on some text
Quote Quote text by surrounding the text with a box, like the [QUOTE] BBCode
Remarks Box Displays a comment, tip, note or warning box
RSS Feed Inserts an RSS feed output.
Sort Sorts the plugin content in the wiki page
Split Split a page into rows and columns
Subscript Displays text in subscript.
Superscript Displays text in superscript (exponent).
Tabs Provides tabs built using the smarty tabset block.
Tag Displays the text between an html tag
Thumbnail Displays the thumbnail for an image
Table of Contents (Structure) Displays the table of contents for the current structure's subtree as part of the page content.
Youtube Display youtube video in a wiki page