To run your own copy of DokuWiki you will need the following:
DokuWiki will run on any web server that supports PHP. Most users use Apache but many others including IIS, lighttpd, Nginx, and Abyss are known to work. When using as a desktop wiki you can also use QuickPHP (webserver and PHP in one file).
PHP needs to be at least Version 5.1.2.
For resizing images either the PHP GD extension or Image Magick should be installed.
DokuWiki should work in PHP's Safe Mode, but depending on your hosting configuration you may need to use the safemodehack option.
Any modern browser should work, but check our browser recommendations.