= The Trac Wiki System =
[[TracGuideToc]]

Trac has a built-in wiki system which you can use for organizing knowledge and information in a very flexible way by [WikiNewPage creating pages] containing an intuitive and easy to learn textual markup. This text markup is also used in all other parts of the system, not only in [wiki:TitleIndex wiki pages], but also in [wiki:TracTickets ticket] description and comments, [wiki:TracChangeset check-in log messages], [wiki:TracRoadmap milestone] descriptions and [wiki:TracReports report] descriptions, even in third-party extensions.
It allows for formatted text and hyperlinks in and between all Trac modules.

Editing wiki text is easy, using any web browser and a simple [WikiFormatting formatting system], rather than more complex markup languages like HTML.  The reasoning behind its design is that HTML, with its large collection of nestable tags, is too complicated to allow fast-paced editing, and distracts from the actual content of the pages. Note though that Trac also supports [WikiHtml HTML], [WikiRestructuredText reStructuredText] and [http://www.textism.com/tools/textile/ Textile] as alternative markup formats, which can eventually be used in parts of a page (so called wiki “blocks”).

The main goal of the wiki is to make editing text easier and ''encourage'' people to contribute and annotate text content for a project. Trac also provides a simple toolbar to make formatting text even easier, and supports the [http://universaleditbutton.org/Universal_Edit_Button universal edit button] of your browser.

The wiki itself does not enforce any structure, but rather resembles a stack of empty sheets of paper, where you can organize information and documentation as you see fit, and later reorganize if necessary. 
As contributing to a wiki is essentially building an hypertext, 
general advice regarding HTML authoring apply here as well.
For example, the ''[http://www.w3.org/Provider/Style Style Guide for online hypertext]'' explains how to think about the
[http://www.w3.org/Provider/Style/Structure.html overall structure of a work] 
and how to organize information [http://www.w3.org/Provider/Style/WithinDocument.html within each document]. One of the most important tip is “make your HTML page such that you can read it even if you don't follow any links.”

Learn more about:
 * WikiFormatting rules, including advanced topics like WikiMacros and WikiProcessors
 * How to use WikiPageNames and other forms of TracLinks which are used to refer in a precise way to any resource within Trac

If you want to practice editing, please use the SandBox. Note that not all Trac wikis are editable by anyone, this depends on the local policy; check with your Trac administrators.

Before saving your changes, you can ''Preview'' the page or ''Review the Changes'' you've made.
You can get an automatic preview of the formatting as you type when you activate the ''Edit Side-by-side'' mode (you have to Preview the page for the setting to take effect). '' There is a [wiki:/TracIni#trac-section configurable delay] between when you make your edit and when the automatic preview will update.''

Some more information about wikis on the web:
 * A definition of [http://wikipedia.org/wiki/Wiki Wiki], in a famous wiki encyclopedia
 * The [http://c2.com/cgi/wiki?WikiHistory History] of the original wiki
 * A wiki page explaining [http://www.usemod.com/cgi-bin/mb.pl?WhyWikiWorks why wiki works]

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See also: TracGuide
