I Want To Create A Discussion Forum Web Site. What Open Source Software Can I Use?

There are many options out there to choose from, depending on what sort of site you wish to create:
Forum/discussion software:
PHPbb – http://www.phpbb.com/
SMF – http://www.simplemachines.org/
Vanilla – http://getvanilla.com/
CMS/Blog software:
Wordpress – http://wordpress.org/
Drupal – http://drupal.org/
Joomla! – http://www.joomla.org/
Joomla and drupal have plugins which allow for small discussion boards should you choose.

http://www.phpbb.com/
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