=== [http://www.mediawiki.org/wiki/MediaWiki MediaWiki v1.24.0] ===
This is the software that users and editors interact with most directly; it is the wiki server software. It is what you are looking at right now. MediaWiki was originally developed for use on Wikipedia and is available under a [https://gnu.org/licenses/gpl.html GNU General Public License (GPL)]. The software is written in PHP, and the installation file is a mere 20 MB.
=== [http://ubuntu.com Ubuntu v14.04] ===