Like most good software that is available on the market today, PHP Wiki too has been written in PHP and it is excellent wiki software that is worth considering, especially as it is also among the oldest as well as biggest engines that works with unique features and does not require any configuration either. In addition, it also has a set of default pages. You can add the PHP Wiki toolbar if you want and there is also an auto signature feature available.
PHP Wiki also has many syntax features including some HTML tagging, plug-ins for math formulae as well as features to allow footnotes, quoting and also internal commenting. In addition, it supports Unicode and there are more than a few languages supported including simple Chinese, Dutch, French and German as well as Italian, Japanese and English as too Spanish and Swedish. It also has email notification and also page redirection features.
Some other common features include previewing, making minor changes, change summarization, page history as well as page index and even plug-in system. PHP Wiki also has decent security and anti-spam features such as page permissions which allow you to lock pages from being accessed or edited, and CAPTCHA to protect against automated spamming bots.
Also, PHP Wiki allows you to store information as text files, or to MySql, Oracle, PostgreSql, and Sqlite and it will run under UNIX, Windows, MacOS X as too with web servers such as Apache, IIS and anything else that supports PHP. It also has powerful plug-ins and is open source and free to use and it runs under GPL.
All in all, PHP Wiki is a clone of WikiWikiWeb that has been created with the scripting language known as PHP, and much like WikiWikiWeb, PHP Wiki too allows you to edit pages while using an HTML form and it also has dynamic hyper linking, full authentication as well as can be themed according to user preferences.