|MediaWiki Handbook: Contents, Readers, Editors, Moderators, System admins +/-|
General Considerations 
Everything related to configuring the MediaWiki software is set in the LocalSettings.php file in your wiki's home directory. Apache reads and processes the settings inside the LocalSettings.php script whenever the wiki is accessed.
Near the top of LocalSettings.php is a line that loads the DefaultSettings.php file. The default settings therefore get applied first. Any of these default settings can be overwritten by a similarly named entry in the LocalSettings.php file if the entry appears after the line that loads DefaultSettings.php. Take care when working with arrays.
Beautifying the URL: Enabling the Apache httpd's Rewrite Engine 
- Please visit mw:Manual:Short URL
The URLs generated by the MediaWiki software by default are pretty ugly; they are hard to remember and contain characters that might disturb search engines when indexing your site.
Since we are using the Apache httpd, its built-in Rewrite Engine can help. It is called mod_rewrite and is also available in version 2; it's also called "the Swiss Army Knife of URL manipulation". It helps us to construct clean URLs.
This module uses a rule-based rewriting engine (based on a regular-expression parser) to rewrite requested URLs on the fly. It supports an unlimited number of rules and an unlimited number of attached rule conditions for each rule to provide a really flexible and powerful URL manipulation mechanism. The URL manipulations can depend on various tests, for instance server variables, environment variables, HTTP headers, time stamps and even external database lookups in various formats can be used to achieve a really granular URL matching (description from ).
Further Information 
For more information about regular expressions either have a look at your local regex(3) manpage or its src/regex/regex.3 copy in the Apache 1.3 distribution. If you are interested in more detailed information about regular expressions and their variants (POSIX regex, Perl regex, etc.) have a look at the following dedicated book on this topic:
- Mastering Regular Expressions
- Jeffrey E.F. Friedl
- Nutshell Handbook Server
- O'Reilly & Associates, Inc. 1997
- ISBN 1-56592-257-3
For further information and help about this module see also:
- Apache URL Rewriting Guide,
- another URL Rewriting Guide,
- mod-rewrite forum, the place to exchange ideas, code, and frustrations,
- Apache Reference: mod_rewrite, and
- mod_rewrite: A Beginner's Guide to URL Rewriting.
Securing your MediaWiki 
Please visit the Security Guide for further information on securing your MediaWiki installation.
Please see mw:Manual:Errors and Symptoms.