Working With MediaWiki

where a software application becomes extremely successful despite being, at heart, a byproduct of another project. (Though it’s not a unique situation — the bug-tracking software Bugzillahas a similar status, and there are probably others.)
    There are some things that do make MediaWiki unique, and in my opinion the most important one is the extension called Semantic MediaWiki. Using Semantic MediaWiki, you can store the wiki’s text as data, and then query that data elsewhere, both in the wiki and outside. But beyond that, it provides an entire framework for structuring data that makes MediaWiki not just a more powerful tool, but, in my opinion, helps to make it the most powerful, flexible knowledge-management tool on the market. This book covers SMW, and its related extensions, to a great extent.
    I first got involved with MediaWiki in 2006, as a direct result of having discovered Semantic MediaWiki. Since then I’ve devoted my career to improving the workings of SMW and MediaWiki in general, and to helping companies, organizations and communities make use of the technology. Around 10 of the extensions covered here, out of over 60 mentioned in the book, were created by me, most notably the Semantic Forms extension, which gets its own chapter; so I could be accused of using this book to market my own technology. To that I would respond that this book represents my view of the best ways to use MediaWiki; I created those extensions because I thought they were features that were missing. Years of working with clients have helped to solidify my views on the most useful configurations. And, hey, it’s my book — any author writing such a book is bound to favor the tools that have worked for them.
    This book will be useful to some extent to average users of MediaWiki-based wikis — Wikipedia and many others — especially the early chapters on MediaWiki syntax and structure. However, the primary intended audience is for administrators: people who are running, or helping to run, or thinking about running, an instance of MediaWiki, and could benefit from a general reference guide.
    The book is called "Working with MediaWiki", because it’s meant for people who are trying to do real work with MediaWiki — whether it’s for their company, for an organization, for a user community, or for themselves. Wherever possible, I try to offer a pragmatic approach, and straightforward answers to the common issues that people experience.

1  About MediaWiki
    MediaWiki is an open-source wiki engine originally developed for use on Wikipedia, and Wikipedia is still by far the best-known use of it. But MediaWiki is also in use on tens of thousands of wikis around the world — it’s almost certainly the world’s most popular wiki software. It’s also most likely the world’s most powerful wiki software, although that statement will require more justification — hopefully this book will provide suitable proof.
    In this chapter, we’ll start with some of the non-technical aspects of MediaWiki.

Available hosts
    Instead of setting up a new wiki on your own domain, from scratch, you may want to have your wiki hosted on an existing website dedicated to wiki hosting — such sites are usually referred to as "wiki farms", or, as Wikipedia prefers to call them, "wiki hosting services". The advantage of such a setup is that it’s much easier to get started -- you can often set up a wiki on a wiki farm, and start editing it, in minutes. Also, for the most part, you don’t have to worry about the software -- you don’t have to set up MediaWiki or any extensions, and you don’t have to update it as new versions come out, because the wiki farm presumably takes care of that.
    On the other hand, there are disadvantages to using a wiki farm, as there are any time that one’s data is put in "the cloud" — to use the current buzzword for online data. There’s no guarantee that the wiki’s contents won’t be lost, if the website in question stops operating, or there’s some technical glitch, or it gets hacked. And if your wiki is meant to be private, there’s the risk that its contents will get revealed due to some security leak. Of course, all the same risks exist on any computer network that your wiki might run on — but on third-party websites, the perception, at least, is that the risk is greater.
    Let’s say that you do want to use a wiki farm, though, and (since you’re reading this book) that you want the software it